[fabguy]

Yes a frame swap is possible, we had to shim the front 1/2 of the cab on our suburban but we used a 1971 c-10 with disc brakes( same, same as yours). The front clip of a 71 c-10 ( if clipping) has almost the same measurements, close anyway. That is what I am using on my 58 fleetside. Rail height is pretty exact but remember that the steering box is on the outside of the frame rail so it is a hard offset for the steering. We notched our firewall so that the center of the steering column is at the bend in the firewall. I will take some pic's tomm of my frame & firewall for you to give you an idea of what to do. Here is a pic of the front of the frame with cab still installed. Not a good pic, but something for now