The gross bracket situation put a stop to any work on Mr. Do, but I still had the G07 to drop into Centipede. That one went in easy since the cab is as it came from the factory and the Atari engineers actually gave a damn about ease of service. I brought the machine up and the monitor showed nice picture. Unfortunately, it was a picture of total garbage.
I cleaned up the PCB edge connector with some Deoxit and removed all kinds of grossness there. Still nothing. Reseating the ROMs on the PCB was next. That got some results!
Still need to adjust the monitor a bit and do a proper rebuild of the trackball. I cleaned it up a lot but the rollers and bearings were neglected long enough to have rusted and the movement is quite rough.
Said to be playable with that crust on the rollers. Must have been a way tougher game that way!