Chasing why the reverse light didn't work lead me to the bulkead connectors. Eventually I noticed a pin in the connector was pushed in ... so far that I couldn't get anything to pull it out.
Fuzzy picture of the offending pin:
IMG_0485.jpg
I removes the 6 bolts that I hoped held the panel (BTW ... to remove the bulkhead panel, it takes more than the 6 bolts!). I managed to wedge the panel far enough open to get a screwdriver in and motivate the pin out far enough that I could pull it with the needlenose. That was luck!!! otherwise I was in for a lot more disassembly. This is all the space available to work with:
IMG_0488.jpg
Now the pin is out ... but what you cannot see, and I didn't notice right away, is that a pin (alternator light) in the lower left connector was pushed in as well. That one had just enough (like 1mm) that I could pull it a bit with the needlenose.
When I pulled them out I checked all the pins by lightly pushing them to make sure they were not going to slide back in.
Intermittent operation/failure ... check that the bulkhead pins are not recessed. My dash battery light works with it recessed, the reverse lights did not. Both could have been intermittent.
Who needs yoga when you have a DeLorean. Working on that part has fully stretched my hamstrings.