Nice work, Ken.
One thing springs to mind, though, I think I'm right in saying that the frame should be supported where it would normally be supported when fitting body panels, in other words, at the crossmembers where the springs attach. Using the rotisserie might (only might) cause the frame to droop slightly which would un-droop when supported correctly.
It may well be fine, but if you find things change when it is up on it's axles and full of seats etc, that may be why.
Mart.