Starting to work on this again. Hoov sent me a bare head with lightboard & wiring a few months back & I came up with relays, a credit unit, & some score reels. Had a bit of trouble with UPS on damage, but with a quart or so of wood glue, it's usable! No problem. 
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RatT sent me a bunch of photos of his Royal Guard backbox that helped too.
It's a slow process tracing wires - I am using colored NEMA wire tags to help keep track of what goes where, labeling as I go. Credit unit is installed, & just starting on the last relay. Getting a lot better at schematic reading (go figure).
Yeah, it looks like a mess as I had to extend all of the wires & did not have any that color matched, but along with the labeling I have made up for each relay a chart showing what color tags go where. Along with the schematic this will help for future troubleshooting.
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Next up is score reels.......
I have no 0~9 unit, & from the schematic it appears that I can just turn off the match feature & that will effectively take the 0~9 unit out of the game. Will save time too, as it gets it's match number off of the ones reel. I won't have to hook those up. -- Well at least until I can scrounge up a 0~9 unit.
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