I'll probably keep on going with this thread, for the rest of the machine, even though the original 'boot' problem is now solved.
As it currently stands I can start a game, but it never kicks the ball into the shooter lane and flippers are inactive. In fact I only have a few working solenoids, mostly just the ones for the drops. Most lights work, not all. Displays are probably going to have to be replaced.
I don't see any activity from playfield switches at all. Actually, the only switches that do seem to be working are the start button and one of the credit buttons.
No sounds at all. Not surprised as the 3081 on the CPU board that drives them is currently removed. I had been getting some sounds during my non-boot situation.
Just going to knock these problems down one at a time. I/O stuff like lamps and solenoids doesn't tend to give me much trouble.