[dataway]

I'm a bit confused about differentials (among other things in life)

So what are the options for a 68 GTO with an 8.2 differential?

What confuses me is that I know certain carrier assemblies will accept a certain range of ratios .. in my case 2.93, 3.23 etc. Parts for these original 8.2 carriers are getting very hard to find.

If I want to keep my original rear axle, but upgrade the differential to something with more options and better parts availability, what are my choices.

B-man has suggested an Eaton posi unit, which looks like a good choice to me ... but what exactly does this change mean? Would more common GM 8.2 parts work with it? Would I be stuck with proprietary parts specific to that particular brand/carrier?

Car is stock, no high HP, and has an auto trans.

I guess what confuses me most is when I see the various types mentioned, like 8.2, 8.25, 8.5 etc ... does this ALWAYS indicated a different differential CASE/AXLE? Are 10 bolt rears always 8.2, 12 bolt always 8.5? etc.

I'm not asking because I'm planning any impending change, it's more of an educational question.

Thanks.