Quoted from Quench:
It's a good idea to change all those capacitors on the switches under the playfield - the caps Bally used are prone to failure after all these years.
Replace with 0.047uF (47nF), 50V or higher caps. They can be sourced very cheap.
Great, thanks Quench, will do.
* I reflowed all the header pins on the displays, and they're all bright and clear now, no flicker or dimness. Only issue I see is P4 display has the final digit completely out. The rest are perfect. I'll look closer at that later.
* Thinking I'll order a new bridge rectifier for BR1 (maybe others and just rebuild that rectifier board a little while I'm at it). I'll get caps for the SDB as well, and do the suggested mods/upgrades as well where needed.
* Have to figure out why the right sling is dead too... little mysteries, but nothing too crazy I hope.
Thanks for all the help so far, it's been great as always! I'll be back soon with updates as I go. Awesome to see this game that sat for so long coming back.