Thanks everyone for your continued help. To @LTG's advice, I'll keep the thread contained here to preserve how the situation is evolving (excuse my etiquette - I'm new around here).
I ran a test on all switches. Most things appear to be firing properly. However this is a summary of what I've found, and the errors I've encountered:
- The magnet test returns a power error when the right gate opens. The opto doesn't seem to register when the ball is within the right gate.
- The opto coffin pop does not open/close if I attempt to trigger it. I believe this is the source of my woes. If I run a game, the solenoid for the coffin pop will fire over and over and over. Lots of free points, at least!
Am I right to suggest I should replace these optos? Should I check a fuse? Considering all I did was replace the flippers, I'm thinking it's more likely I just pinched something somewhere... But I'm not seeing anything visually troubling.