I had my passenger door off a few weeks ago. I opened the door part way, put a floor jack under the center of the door with a 1x2 wood strip between the two. Put just enough pressure to hold the wood there and unbolt the hinges from the door. You can slide the door off the hinges pulling the jack back. Just make sure you have the door balanced on the jack. I took it on & off about 3 times while replacing the lower hinge pillar.

1957 Chevrolet 1/2-ton Stepside LB in the Gallery
My Photobucket shots

The person who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself." - John Stuart Mill (1806 - 1873)