cap swapping 2x4 to 4x4

[munkjeep]

I have a 69 GMC 1/2 ton 4x4, what all cabs will interchange? will a 2 wheel drive cab work as long as it has the shifter pan in the floor board? I have a 72 GMC ton truck, will that cab bolt up to 4x4 frame with no problems? thanx for your help, I am trying to decide what route to go, replace the cab corners and rockers or swap on a rust free cab,but junk a ton out in the process, or should I look for a cab in the junk yard.