[jimib]

Hello All,

Got my GTO back after 5 years in storage. The enthusiasts on this form helped me rebuild the engine which is running strong today.

I’ve read and still reading threads on body work. I want to start by replacing the floor pan. Before I do any demolition, I need to read more and hopefully gather info on this thread. My questions are:

1) How do I separate the floor pan from the rocker panels? (Eastwood has a part called a “seam buster” but I think a chisel and hammer would do the same thing).
2) What floor pans are easiest to install, a one piece, two right and left halves, or four piece sections? (There’s rust holes in all four pan sections but good metal around the rust, 4 pieces seems easiest and least expensive to me. I think a one-piece would be hard to manipulate).
3) Can I repair the rust hole in the rocker with new metal or should I replace the entire rocker? See pic. (Trying to replace the rocker panels seems intuitive. I believe I would have to support the body up and off the frame).
4) Would this be an opportune time to get at and replace the body mounts with the floor panels out?

Hopeful the pictures will help give a description of where I’m at. I’m not sure of the integrity of the floor braces but from what I visualize, they appear to be okay.

I’m buying the tools as I need them and gather advice. The first semi-major purchase will be an air compressor. The big box stores and Northern Freight have 60 gallon compressors available for more or less $500. They appear to have favorable reviews. After the compressor comes the MIG welder.

Thanks in advance and great to be back on this site after a few years.
Jim

[Old Goat 67]

Welcome back Jim,

Good to see another 67 coming back! We'll be here to help.

Question, just how much of the floors are bad? Wondering if I'd replace the whole thing or just cut some patches out of the new pans to replace sections?

Less work I would think, as long as the surrounding metal is still good.

Rockers look like a different story.

Charles

[400 4spd.]

Someone has replaced part of that rocker (badly) before. Plan on cutting it out and starting new.

[webfoot]

To separate the seams you need to first use a spotweld cutter, and then the seam buster. Hammer and a putty knife works well, assuming it has a metal end to it. I like the wivco spotweld cutter, it doesn't have long teeth to break off.

[hugger]

I use the Snap-on brand spot weld cutter myself but I own a body shop and do a lot of panel cutting. I can however once the depth is set cut about 10 welds in 30 seconds, and that is moving across some metal area. As far as the 1vs.2vs4 piece floor pan goes the 4 is made for the man who got lucky[no not that kind] and only has a small window leak and has one pan with a little rust. I did a 69 Camaro and used the 4 piece pans I and was happy and them on my 68 LeMans convert I used the 2 piece pans and liked them as well they would be a little harder to move around in a tight space but I have the drop top so that was not an issue. I put my pans in about two months before the one piece pans hit the market, I wanted to cry. On the rocker situation, I would be as sure as you can be that you have cut away all of the rust by doing whatever means that is if it is replacing just a patch or the whole panel,so be it. I would probably try the bushing by doing one side at a time, unless you have access to a two post lift then you can take the body off the frame and do them all at once like I do. I use my two post to change frames and cabs and remove beds[truck]it is one of the best shop tools I have ever bought.

[Judas]

On the 4 v 2 v 1 piece patches. Just my 02 since I've only used the 2 pans of a set of 4, but have read a lot about the different types. Basically, the more metal you cut out, the harder it is to get things lined back for replacement. Doing a full floor, alone, would scare me due to alignment and just having to work with this big piece of metal. The 4 is easier because you are working in sections. However...you have a lot of damage there. I would probably opt for the 2 piece halves and do one side at a time. Again, just my 02. If the other rocker is good, I would not bust the seam on that side and just cut like 2 inches inside to leave a 'lip' for alignment.

I'd think it would be a great time to repair the body mounts, but not familiar with that body style.

Put me down in the 'probably gonna have to replace that rocker' camp. I suspect there is a lot of hidden rust inside there. Read up on this first because the rocker is typically a structural member. You car is a hardtop, so its not as hair-raising of a prospect vs a convertible, but there could be a devil in the details.

Good luck!

[jimib]

Thank you ALL for the input; I’m gaining excellent knowledge here.

Judas: Good point on the floor pan alignment issue, I will buy the 2 halves. Yes, a lot of damage but the tranny tunnel appears solid. The outer rocker is basically solid accept for damage towards the front of it (drivers side for now). I think I can weld in new metal and it won't be seen anyway. However; when I cut out and looked through the damaged area and looked beneath the car, I could see the inner rocker has additional damage. I’m assuming I have to cut out the outer to get to the inner. I guess I have to make this cut somewhere near the rear of the door to separate it from the quarter panel. This is why I included a pic here. Certainly have to read up on this topic.

Finally found a spot weld cutter locally; of all places and the last I checked, Harbor Freight. I might last a few days until I receive a decent one from online.

[Judas]

Thanks for the compliment. One other thing I will mention. I am not familiar with the coverage of the replacement panels for this year. If your tranny tunnel is solid and the rear pans are ok, the standard patches might be enough. I saw you have rot out on the pass. side, rear drain hole and was thinking halves. However, on my year the standard pans reach pretty far back and the rear pans are just these little 'cookie sheets' for the wells.

I dont want to waste your money needlessly. Also repro parts tend to be thinner (regardless of claims otherwise) so if you can salvage the original trans tunnel, I would think it would be stronger. Sorry for the conflicting advice but I dont want to steer you wrong.

-J

[jimib]

From Performance Year:

RP1284C: full left hand floor pan (70”) $109
RP1285C: full right hand floor pan (70”) $109
---------------------------------------$218
However, the pans beneath the seat have rust damage (new pic included)
RP1283R: right rear seat panel $70
RP1282R: left rear seat panel $70
------------------------------$140
+
-------------------------------$218
=
-------------------------------$378
So I’m looking in the area of $378 which does not include the braces which I may not need; don’t know yet. This is cheaper than the entire one piece pan.

The low budget Chinese “spot weld remover bit” worked okay thus far I got separation from pan to rocker. My problem though, are the spotwelds on the floor back seat area which are up against the interior of the car. Difficulty getting my drill in there as it is forced on an angle. I need to buy an angled drill.

If I may deviated from the subject of the thread; I’m buying a compress in the morning, either a Husky 60 Gal (Home Deport) or a Puma 60 gal (Northern Tool). Both have the same CFMs, have high user ratings, and price is somewhat close. Can anyone briefly share info on these items? (Then back to the main topic) A compressor could make this job a whole lot easier.

[jimib]

Hello All,

I’m receiving my floor pan tomorrow. I’ve read many threads on floor pan installs such as making cuts based on the fitment of the new ones places over the old one for a lap joint. I feel comfortable and no questions at this time.

However; how should I prepare these panels for primer and paint? They come with oil on them, I guess to prevent rust. A pneumatic sander, a sand blaster, a degreaser, a combo of both?

Also, I removed the fenders and wheel wells. My goal is to paint the entire wells and inside of the fender, the front clip (removed) and the stuff that encapsulates the heater core. I think I may need a sand blaster but never used one before.
Please advise me.

Thank you,
Jim

[400 4spd.]

The oil can be washed off with a degreaser or a solvent, like thinner. Personally, I prefer to sand both sides with 180 or 220 grit and then spray the underside of new pans with epoxy primer. It's much easier to do before it goes in the car.
After welding/grinding, the top side gets epoxy. I deal with the burned spots underneath later while on the lift.
As a rule, I usually find that parts with black EDP coating are better quality fit-wise than bare parts.

[zephyrracer]

Glad your posting you restoration, looks like what I'm getting ready to go thru, lots of luck.

Gregg

[jimib]

My floor pans arrived today and the rear seat to trunk sections are in transit. They appear to fit nicely inside the cab. They are not welded in yet. However; I’m still fearful and uncertain of where to start cutting at the rockers. Front and rear sections I’m not too worried about. First I need to understand the anatomy of this operation, so the “Assembly Manual” and “Fisher Body” manual I ordered will arrive tomorrow. As I understand from my visual inspection, the rocker panels affix to the frame via the body mounts (which I have new) and the floor pans are spot welded to the rockers? Yes or No? It may be in my best interest to replace the rockers as well. Still, if I did this, where do I make the cut where it joins the rear quarters? If I’m replacing the rockers, does the entire body need to be support off the frame? I think it should since I’m also replacing the rear floor brace.

Thank you all, I'm taking it slow on this issue

[webfoot]

The floor gets spot welded to the rocker panel and to the floor braces. Assuming everything still has paint on it, if you buzz it with an abrasive disc and remove the paint you should be able to see spot welds a lot easier.

Rocker panels don't attach to the frame at all. They attach to the lower cowl/floorpan/quarter panel.

May want to spend some time researching and practicing rosette welds too as they are a bit trickier and require a lot more heat than tacking panels together. Nothing worse than spending time redoing these if they don't hold.

[Dave R]

I second the practicing of welds. When I did my apprenticeship, all I did for the first 4 months was sit in the welding booth and practice on scrap metal.

I like to sand off the EDP coating in the areas where I am welding. Back about 1/2" from the edge of the weld or in an area of plug welds. I use a thin coat of weld through primer on the areas where the metal won't be accessible after the weld. Use a clean wire brush to clean up the welds. It's easier if the weld is still warm. Don't use a brush that has been used on greasy parts. I have a wire brush dedicated for just that.

Your other choice is how you will attach the panels - lap weld or butt weld. Lap weld is easier, takes less welding skill and is much quicker. I always butt weld - I can't ever seem to take the quickest route.

[RedDirtRoad]

Why are you using 2 piece floors when 1 piece are available

[jimib]

I certainly see the spot welds and removed about half thus far. Certainly I’ll practice welds on scrap metal prior to the floor pans but I’m not close to that yet. I finally have time this weekend to hopefully remove the entire rotted floor pan. I have a replacement rear floor brace. Removing the original rotted one and the body mounts I think is going to be a challenge and a learn-as-I-go process.

I opted for two halves (floor pans) rather than a one piece because I read numerous post that a one piece is difficult to maneuver and manipulate with in the cab area.

[webfoot]

Practice a bunch of rosette welds too, you'll need to turn the heat up for those, compared to what you'd use on panel replacement.

[jimib]

I’m at a point in this project where I could use some advice. This is more time consuming than I anticipated. I could be spending too much time trying to salvage the middle and front body braces which perhaps should be replaced. Any opinions based on the pictures on the driver’s side of vehicle? If I decide to replace the inner and outer rockers, where should I make the front and rear cuts?

[400 4spd.]

Originally Posted by 400 4spd.

Someone has replaced part of that rocker (badly) before. Plan on cutting it out and starting new.

Maybe cut away the part I mentioned before and see what is underneath. To replace a complete rocker, you see that it extends under the quarter panel and it attaches to the rear outer wheel housing. It also has the hinge pillar dropped over it at the factory, so you would need to either:
cut away several inches of the lower pillar area to access the rocker welds, or
cut the rocker a little bit away from the pillar edge and section the new one in. That would need further instruction.
Again, cut away the piece that is capped over your original, and then you might see how much you really need to replace.