It'll depend on what the rearend that is in it now is. If it's a Truck 10 or 12 bolt, the axles shafts can be swapped (no need to change the backing plates, they are the same), but they will require shortening and regrooving for the C lock as the '70 and earlier axle housings are slighly narrower. I beleive the amount they need shortened is about 3/4".
