Good repeat sources for help:
https://www.mikesarcade.com/arcade/
https://www.myplacearcade.com/index.php
https://www.arcade-museum.com/
https://forums.arcade-museum.com/index.php
http://www.arcaderestoration.com
https://homepinballrepair.com/pinball-electronics-tutorial-basic-electronics/
http://www.thepinballfix.com/tips/bally_lamp_fixes.html