Thanks, Gene. What a lifesaver you are. I was getting ready to throw in the towel and replace the unit. It never occurred to me that these things are matched. I'm sure I have them cross-wired. I can't find a wiring diagram that tells me which burner is which, but I guess I can trace the wires.
And thanks for that post on the physics behind the igniters. That's a great write-up.