The contraption in action
To review, I finally had to give up on making a gambrel roof, so I opted for a vaulted ceiling. But this required me to raise the level of the walls in order to preserve head space and floor space in the loft. So I'm building and installing half-wall sections above the main walls.
I'm building them without paneling (except for the corners) in order to save weight. I'll put up the paneling after they're all installed. I especially wanted to avoid weight because getting these things up over my head on the walls is a challenge. There's only me to do the work most days and even if I had a partner, lifting these wall sections up and nailing them in place would be difficult.
But, being a man of infinite-resource-and-sagacity, I had a plan. I previously built a tripod with 12' 4x4s to install the massive beams that undergird the whole house. Today, I dragged it out and added extensions (two 4' extensions and one 8'). Then I put my block and tackle to work. It takes a very long time to position the contraption for each lift, but it raises the wall sections almost effortlessly.
As I've said for years, I may not be much of a carpenter or mason, but I can build anything with rope and spars.