Progress on camp, ran a new ground wire that fixed a bad ground problem on four duplex receptacles. I still have four receptacles that show bad ground, but they are the same circuit, and one of the now-good receptacles is near the bad group, so worst case I shove a new ground wire
through to the outliers, if I don't find an obvious missing/poorly connected ground. This exercise is also giving me the chance to replace beat outlets in general, a good thing, some stuff does need replacement after decades.
A gorgeous weekend coming up, hopefully I can replace that one section of wall that needs to be redone. Two windows in it, adds a PITA factor getting the cutouts and flashing right, but I should be able to get it at least most of the way done. New sheathing, Tyvek, siding, 12' x 8' area. I'll skip off the electrical for now, since it's in an overall safe state and the problem area isolated, to start by removing the interior wall (70s cruddy false-wood panels, a bit of water damage from the exterior problem, happy to rip and replace them).