You seem to be good at soldering and willing to work! I always advocate rebuilding solenoid driver boards as they are almost always saveable. You have bought the 2 large capacitors, which is good, but I would recommend rebuilding the entire 5 volt and high voltage sections on the board using the kits found on Big Daddy's site here: http://www.bigdaddy-enterprises.com/. You only need the "half kits" for both the 5 and high volt sections.

Those displays aren't really trying to tell you anything, I would check the left 2 connectors on the mpu. Re-pinning them will probably be required as the pins have worn out over all this time. Having the playfield out of the game shouldn't really effect what the game does at start up. Everything else looks great!