I think I finally resolved my issue with the lights going out and the flippers dying.
At PinMonk's suggestion, I unplugged the CN15 connector on Node board 8, which is the lower playfield lights. By disconnecting wires to the plug and only running one color of lights at a time I narrowed it down to the red lights. I then inspected all of the sockets and red bulbs on the lower playfield. That turned up nothing. But to get to the last two I had to remove the flipper mechs. When I did, I noticed this tiny nick in the insulation of the wire leading to the red bulb under the right flipper mech. It was from where it had been pinched the metal edge of the mech being installed. My eyes aren't good enough to see if the cover was cut all the way through, but it looked like it could be enough to be causing the short, so I covered the wire and put a strip of duct tape along the metal edge of the flipper mech.
I then played a quick game with no issues.
My next game was epic (for me) and went about 30 minutes. Like someone else noted on here, it seemed to happen a lot during multi-balls. For me, Headlong Flight was always a killer (I guess because there's a lot of red lights). On this game I got every multi-ball and Headlong Flight twice with no issues. No dead flippers. No loss of lights. New high score.
Of course, two games isn't a solid test, but its the longest I've been able to keep the machine running since I unboxed it three weeks ago.
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