The manual and, as you've indicated, IPDB show the blue/black and orange/black as being the correct colors for the slam switch. This switch is wired in series with the ball roll tilt switch (orange/black wire). As others have said, you need to look around (on the tilt board, bottom board, head) for evidence of the hacks - those wires being spliced, the source of the new slam switch wiring, any additional wiring tie wrapped to existing bundles and other general monkey business. You have said that the insides are in good condition, I'd think the changes would stand out.

This certainly qualifies for the hacks and door bell threads!

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That's correct, refer to the manual page in post #15, #2 Coin Chute Switch wiring.

From the same manual page pic in post #15, the black and orange/black go to the two sides of the Ball Roll Tilt Switch and the purple/white attaches to the metal frame of the roll structure to ultimately connect to the tilt bob shaft.

I've attached the manual page with the knocker wiring, wire it to match the diode orientation.

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