I used some camper jacks.found them at a garage sale for $25 for the set.built a beam with 8' 2x4s and screwed some 12" plywood to boathouse sides. Pulled the doors and ran the beam through. I fastened the beam to the camper jacks so no chance of the beam coming off the jacks.worked sweet . For the rear I used rope from the top rear door hinges to screw eyes in the garage rafter, I was going to use small block and tackle but found it wasn't vary heavy and was able to just lift up on the body as I pulled down on the rope. Working slowly one corner at a time it was easy and safe .
Once the frame was rolled out I lowered the body on to stands.