How to lift drywall for ceiling up onto a scaffold?

Bill Crowell said
Can't use a regular drywall lift for my shop ceiling because it is too high, so I am going to install it from a 2-level scaffold instead. The only problem is, I'm stumped about how to lift it up onto the scaffold. Would any of you guys have any bright ideas about that? Thanks very much.

Not sure if this would help, but I had a similar problem when I replaced the roof on my 150 year old house a couple years ago. The joists were swayback - like 3 inches in on a 16 foot plan and the sheathing rotted. So I had to remove all sheathing, sister the joists and put new plywoid sheathing. The edge of the roof is about 20 feet off the ground. I had scaffolding hardware they sell at the big box stores that use dubole 2x4 posts. I did this piecemail over the summer by myself occasionally with a helper, but more often alone.
In amy case, I had a similar problem as you have in that I needed to raise 5/8" sheets of plywood up to the scaffold. To do this, I rigged up a thing with a c channel that I would place at the bottom and a piece of angle iron with eye bolt mounted at the top. I would then use small rachet straps to hold these to the panel. Then I bought a hand winch and mounted it to the double 2x4 post that held up the scaffold. Then I would just reel it up. Maybe you could do something similar, but youd probably need at least a 1/2" plywood backer to keep the drywall from cracking/breaking while you raise it. Not sure if this woukd help, but thought I'd throw it out there...