Most of the nuts came out with minimal force, but the last one just spins in place. I tried rubber gloves, painter's tape, and duct tape to get a better grip. I'd rather not cut a slot in the domed nut if there's another good strategy.
The rest of the restoration underway:
I'd get a dot of rubber a bit smaller than the nut, and a hammer impact driver on the screw.
https://www.harborfreight.com/heavy-duty-impact-screwdriver-kit-9-piece-58151.html