I managed to feel recovered enough from my end-of-week cold to be somewhat functional today. I got out (masked ofc) to a hardware store to get a couple of fixtures and boxes and replaced a poorly-setup fixture and switch in the furnace room.
More of that for tomorrow – pacing myself here. Another fixture and jbox to change and that'll give me the slack and config I need to put a controllable switch on an outside receptacle, finally.