The right slingshot on my xenon was stuck on. After doing the tests, found the SCR bad, replaced SCR, and slingshot would not work. After doing the other tests-checking coil, re-checking new SCR, and switches, I found when I jumped across the switch diode and made the switch, it would fire. Assuming the diode was bad, I replaced it with a new one (1N4004), soldering it in the same orientation (unbanded end on wire terminal). Still didn't work. Out of ideas, I switched direction of the diode and it works, but occasionally the coil sticks until a bumper or flipper is hit, then it releases. Still very confused as to what is wrong. Any ideas would be appreciated.

yes, completely smooth. Replaced coil sleeve and cleaned / polished plunger. We can rule out mechanical, I think.

I'll have to check. Gimme about an hour, still at work.

Ok, I'm back. Sorry about that, silly bastards actually expect me to do something when I'm there. The voltage at the coil is 41 volts.

1. yes new coil diode in the correct orientation.
2. yes, ran the diagnostics, switches and coils both clear.
Here's the kicker: new switch diode only lets the coil work when the diode is in backwards. ie: the band on the white wire connection instead of the leaf connection.