Download the WPC schematics manual at the link below and follow the wiring for 120 volts.
https://usermanual.wiki/Document/WilliamsWPCSchematicmanual.1930250976/help
Wire colors are all there. Use the old 9 pin connector to determine pin numbers on that connector. GPE is probably your best bet to get parts and tools needed to get it straightened out.
https://www.greatplainselectronics.com/
Also, next time you ask for help, go ahead and throw the name of the game in your post. Kinda important.