First off, great work doing this yourself on jack stands. That’s got to be a tough job. Judging by the marks on the new bearings I’d say you used BE. Excellent choice! I really want to know if rod bolts on cyl1 were only finger tight that can’t be possible. You would have had major issues prior to noticing. The oily plug is probably from a leaking spark plug tube above it or improper torque on that plug allowing it past. An oil cap won’t have anything to do with an individual spark plug. Did you drop in new plugs while you were at it? Cheers for the good work, but get some better beer than that founders all day stuff…
It’s typical for a flush mounted transistor heatsink plate on the back to be fully soldered to the board requiring great heat to release them. Usually a hot air solder station is required. Do you think this is the case or was it epoxied on the board? I’m tempted to go dig up my old TAs and see how they were done.