After you are done blasting/priming/painting the underside by whatever method you choose to use, I would suggest that you put the body back on the frame and make sure that all of your body-to-frame spacing measurements are to specs prior to body work.
It would be a monumental task to create a "stand" which would duplicate the frame. It is crucial to have the frame under the body to perform any body work, as there is a huge probability that there will be distortion from it. Just by removing that huge structure from the frame will likely result in some distortion that you won't be able to detect until you go to put it on the frame.
Carl

Last edited by 52Carl; 03/13/2017 12:25 AM.

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission