I'm pretty sure either the machine is jinxed, or I am.
Was doing a quick adjustment and fried the entire row of switches on the right side of the playfield.
Joy to the world.
The worst part is - I've done this two times before!
"I better turn of the power this time!", and so I did. Did a quick fix and turned the power back on, realized I needed to do another quick fix and BOOM. Short circuit.
I guess I should be thankful the switchboard took the hit and not the CPU, myself or anything else that's hard or expensive to repair! Knowing what I know now I should have made the IC's buffer/overload protected or easily replaced by using sockets. Again, next time.
When doing a quick damage control I noticed that one of the solenoid cables had come loose, so I figure I'll do a full go-through on the machine in a couple of days.