My Terminator 2 almost always kicks 2 balls out of the trough to start the game. I've tested the switch there in the test menu, and it seems to be working fine. Any suggestions?

Yes, there are 3 balls in the game. As far as I know, that's the correct number.

I played with all the trough switches for a bit and I finally figured out what was going on. I was focused on the shooter lane switch because I suspected that it was detecting no ball there so, it kicked out another. But the one with the problem was the leftmost. As I slid the balls back and forth, I could see that it was occasionally getting stuck on. This was leading the game to think that it had an extra ball in the trough which is why it kicked one out. A little trial and error bending the wireform seems to have gotten it working much better.

With that out of the way, I decided to tackle replacing all the bulbs with LEDs tonight. It was going well until I shorted something out while trying to replace a hard-to-reach flashlamp. So, now my flashlamp circuit isn't flashing. That's enough for tonight.

Thanks everyone!