'64 4X4 Frame Interchangeability

[5Tractorguy]

Got a quick question for you guys. Due to certain circumstances I have to find another entire frame and drive train for my '64 GMC 4X4 resto (3/4 ton 8 lug). Would one from a 67-72 be the same? Will the cab, bed and other components bolt to it correctly? I would assume I'd have to make motor mounts for the V6.....

I would much rather find another period correct one (Chevy or GMC) but they are mighty scarce here in New England.... Would even consider a road trip if anyone has any leads....

Any help would be appreciated...