I plan on using a frok lift myself only because of access through family. I remember a thread a while back when someone used a big floor jack, alot of wood pallets, and 2 12' 6x6 studs. He unbolted everything, started jacking the tub up enough to get the stud under it and put the stud on the pallet on the outside of the body. Everytime he lifted it up, he just added more pallets. He ended up with it like 6 ft off the ground to roll out the frame, motore and all. He and 2 of his friends swapped bodies in a 3 day weekend his way.
I'll try to find the thread but it might ake a while.