Getting ready to paint my Merc, was just going to paint it with doors on, but lately have become convinced it would be better to take them off.. Typically I work by myself, and need a little help in how to handle them, without beating the paint up.
I used my engine hoist with a nylon strap in the middle to balance. Use two straps for more security.
I have built a cart out of wood previously and put rollers on the bottom allowing me to roll to and from.
Before you take your doors off, make sure to drill 1/8 holes thru the sheetmetal into the hinges to use for reinstallation alignment.
you could use an offroad style/farm jack or get a monkey on a stick https://www.autobodytoolmart.com/keysco-monkey-on-a-stick-77043-p-10485.aspx
When I hung my doors, I was still in my old dirt floor converted carport where the car was totally built, so something on rollers wouldn't have worked that well. I did however use a nephew and a floor jack to help a little with support and adjustments. I wasn't aware of the tip I posted above when I dis***embled the car a zillion years ago, so I had a lot of cussing going on during the re***embly!, lol.
Thinking of trying one of these https://www.eastwood.com/e-z-rest-door-hanger.html also a set of these https://www.eastwood.com/eastwood-pin-alignment-system.html, but was hoping for a miracle, I guess. I am in a garage, but it's old and the floor is in rough shape, which rules out a few options
Let me back up on something I suggested, and that being the size of the drilled holes. 1/8 is kinda small, what I actually use for the "pins" is an automatic center punch (available at Harbor freight). Super handy tool for many things, but in this case, the pointed/tappered end makes it easier to get the holes to align in the two pieces. Get two of these and it'll eliminate the eastwood pin alignment set......a few less $, and tools you'll find many uses for afterwards. I use them alot for burnishing stuff, woodworking, and even occationally used for what they were intended! Just drill your hole sizes to match the center punch.
When I was reinstalling my doors I had predilled an alignment hole and used an adjustable stool I had. Put some nice soft towels on it and put it under the door 3/4 of the way back. I was able to hold the front to align the hinges and put the bolts in. It worked well for me.. A stool like this https://www.harborfreight.com/catal...tured+Weight,f,Sale+Rank,f&q=adjustable+stool
I drilled my doors and hinges using a 3/16" drill. I had some drill blanks that size, but I had help with mine, took us about 10 minutes to hang and adjust each door.