Get the boards individually solid in the following order:

Rectifier
Solenoid Driver
MPU
Lamp/Sound

Pinwiki has a nice walkthrough of the order to go in but basically you work each board in order. You probably have a blown diode in the high voltage section on the rectifier board, either replace the entire board or at least rebuild it (I think it's best to replace at this point I use the weebly board bought as a kit to do this)

Do you have the displays unplugged.... if so, yes, the high voltage section on the solenoid driver board likely needs to be rebuilt.

Rebuild the entire section, not parts of it.