[Rockcrusher-M22]

Hey guys, I am in the process of purchasing parts to build my 462. Here is what came with my initial purchase.. Package deal

1970 YH 455 .030 (Block fresh from machine shop)
Standard 4.210 Stroke "N" Crank .010/.010
Kieth Black pistons (KB347.030) Dome 0cc (New in box)
Comp Cams XE268H (CL51-223-4)
5C-8 Cylinder Heads (Super clean but unsure what's been done to them)
Melling high volume oil pump

I'm looking to purchase the remaining items from Butler

Eagle Rods
Bearings, Rings, Gaskets, Push Rods, Rockers
Steel Main Caps (Do I even need these if I don't go over 600hp?)

I also have an opportunity to pick up a set of 6X (96cc) also right out of the machine shop with new valves and springs. Many would say these are definitely better than the 5C heads.

My HP goal is to be somewhere in the mid 500s. Compression should be around 9.4 with the 5C heads and 9.7 with the 6X. Am I on track to reach this goal? Is the cam right for this combo? It will be mated to a M22 and 3:55 rear in a 69 GTO..

Any advice is greatly appreciated. I'm a little stressed and don't want to waste money. Thanks!