I have a 1951 Chevy pickup that the previous owner tried to put a V8 into and ruined the frame. I also have a 1978 GMC 4X4 pickup that I was thinking of swapping the body’s with, I know that I will have to either extend the cab or shorten the frame by 15 ½” or even trade out the stock bed with a flat bed and leave the frames alone. My question is if anyone here has any experience in this type of swap?