Use JackStands
When I had my 89 23' with the wing keel, I would get a couple of jack stands from the boat yard. When doing under the rear bunks, I would drop the tongue all the way down, place the stands under the stern, 1 on each side, then crank the tongue back up to drop the bunks out of the way. When the paint was dry, I'd drop the tongue back down and remove the stands. When doing the front part of the bunks, I'd crank the tongue all the way up, place the stands under the bow sections, then drop the tongue to let the bunks fall away from the hull. Paint, let dry, then crank the tongue back up and remove the stands. Worked well. I kinda do the same thing now with my 38.5, only I use a 12ton jack to lift the cradle before setting the stands.Good luck