Finding a 67-72 4wd frame is the way to go, finding a 71-72 is best, disc brakes, better gear ratios too. Buying or fabing spring hangers for your frame can be a pita, although can be done. I see it this way, you have a separate frame to build from the axles up, frame, paint, brake work, ect, at your leisure. Your 2wd can still be driven until you are completely ready to do the swap. They come up from time to time here in the salted northeast, I would assume you can find some in that nice dry desert you have.
