I installed a new switch and I now have passenger side brake lights.
Driver’s side still inoperable.
I started removing the instrument panel and it appears that I have to drop the steering column.
My suspicion is that either the emergency flasher or light switches are bad.
Flashers work, except for the driver’s side rear.
Headlight switch also makes the turn signal act odd on the driver’s side.
I have the manual and a laminated schematic.
I will post an update when I get back to working on it.
One other oddity is that the instrument panel turn signal indicators seem to be wired backwards, in that they are on when I put the ignition switch in acc or run.
I don’t think there’s a grounding problem, but will check them as I go and keep it in the back of my mind.