I get 32v in tilt or game over (from the 2 red/white wires)
0v when game running/ball in play - pulses to 32v when the score motor runs.
The red/green wire (top left switch) should go to left hand backbox plug - bottom row, 4th from the left.
I had a shit-load of trouble getting that AB interlock relay to work properly - it's a real PITA to get right.
Hitting the "AB" interlock with a screwdriver will force the game to run if the score reel switches are out. Maybe the previous owner/fixer bent something in there?
(I'm looking in the schema - the AB is part of that circuit)
EDIT: The red/black wire from the left hand switch goes next to the red/green....
SO - backbox plug - 3rd from left, this also has another lighter colored wire in the same terminal...
This (slate/blue?) wire goes up to the score reel relay switch "F" and then loops to the other score reel relays...