@C10-C90 Bill, I just looked at the VIN again, it is a W. I'm not sure what that W means at all.
@3B, Thanks! I am pretty sure it's a 350 but 100% sure. I'm sure there are casting markings to look up. I do know that the timing is not the same as what the standard 350 calls for. It is off my one position, counter clockwise.
I do know that the brake parts are proving to be challenging. When I look up a 1972 GMC CE, CG, CS, SE, SE, SG, SM, SS, TE, TG, or TM 5500, the only master cylinder I can find doesn't resemble mine at all. Mine is much bigger than the one they call for. I found one that looks like it by looking up tucks in the series such as the HM, JM, RM, TM, AND WM 7500. It comes up as a Raybestos part number MC36346. Does anyone know why my truck as a 2 ton would would have a larger master cylinder?
Also if anyone knows how to upload pictures to the forum, I would be glad to share the progress I'm making!
