Interesting. I know you’re an experienced EM guy, so I won’t ask dumb questions like whether you’re counting the switch stacks from the right end

No chimes makes me think it may have been an export machine? Or a custom config to run quiet? I have seen references to machines with no chimes before. It’s usually from someone looking for a chime unit

Any chance this is the add a ball version that someone swapped the replay backglass into?

Just trying to think of why the schematic wouldn’t match. I’ve found the Williams documentation to be very good.

Good luck,

Dave