I once got the bright idea of converting a 69 C30 to a 4x4 using my rotted out 72 K20 drive line. Trust me the frames are not the same. Now I have seen some trick 4x4's out there where a guy put leaf springs and the axle under his 64 1/2 ton short bed. He added longer rear springs to even out the height. Anything is possible. Just depends on how much fabricating you want to do. It's not a bolt in job.
As far as Bowtie65's question. I have wondered the same. If the newer chassis is straight or nearly straight where the cab sets on, I am sure it could. I know 73-87 frames raise up under the seat area of the cab so 60-66 cabs don't sit right on that. (Last weeks lesson learned)
