OP

Quoted from yzfguy:

Hesitant to say it's fixed, but I reseated some connectors and Rudy's jaw and the optos have been working great. Hopefully it was a loose wire in a connector, I just wish I knew which one in case it happens again
Ordered pinscore display to fix the display issue for good.
Thought I made some headway with the screech, but now I'm not sure. I did some reading about a bad capacitor on the speaker connection causing noise, so I disconnected the cab speaker and there was no screech when I turned the game off..... Then I realized that there is no sound at all with the cab speaker disconnected. .. I thought the speaker panel speakers would still work?
Tried hooking up a different cab speaker with no capacitor, and it works, but the screech is back on power down. I wish I hadn't skipped science class back in the day