I put a bit more epoxy filler on the steering wheel, in a few places I had previously managed to miss. Then I sanded it, buffed it with my power buffer, and gave it a coat of floor wax. It doesn’t look perfect- the color of the epoxy does not exactly match the original plastic- but it’s a lot nicer than when I got it.
I bolted the steering wheel in place and installed the headlight/horn switch, which has a long shaft that runs all the way down the center of the steering column. Then I bolted the headlight bar to the fender braces (without the fenders, which are back in the attic), and hooked up the headlights and horn. The car is more drivable now, with working lights and horn. Those things are functional but unrestored, so eventually they will have to come off again.
I guess the next step is to start test-fitting the interior panels, and do any necessary trimming or adjustment.