Well after checking a bunch of wiring and trying to match to the schematics, I went back to Occam's Razor. Even though I couldn't see it, and I'm still not sure I understand why, it was (at least) one of the 4 switches on CAM 1, stack 3 that was causing the problem. As I showed previously and I think you correctly identified, a previous owner had a completely different adjustment on the stack and they were using something (picture above) to force the blades abnormally high to support the make / break adjustments. When it fell out, I forgot to look at the proper alignment of the stack. While they were normally open, they were also never closing. Since they didn't close, they didn't indicate to something that the switch activated and so the score motor kept running.
My current problem (again, one of my own making) is that the 4 drop targets never reset. I was messing around with one of the targets and I wonder if I messed up a switch there. Although I would expect them to reset anyway during a game reset, but that's not happening either. If I understand the schematic, it should only take either the slide reset or shot 13 to send power to the 2 coils through the score motor switch c-3.
Please let me know if you read the same in the schematics.
I don't think the targets reset if you knock them all down. Please let me know what you see on your game or the schematics,
Once I have this resolved I need to reinstall / align the gun and board. I was having a problem with the chain length and the way the gun was installed, you could move it back a little too far and that would send the stylus flying. From what I can see, the stylus just sits in the spring and floats, there is nothing to attach it to the arm so it cannot fly off.
Is that your experience?
Thanks