Stu,

I restored two original playfields and the ball size in the Queen's Chamber was standard. I'm going to investigate this some more, but do you think the previous owner of your game added the bigger ball because the clear retaining plastics were widened a bit from play, and not holding the ball anymore?

Midway connectors. Don't forget to disconnect the ground braid in the head. Congrats on the Centaur purchase!

Geez the more I think about it the more I'm not sure every harness has a disconnect. No Ballys here to check.

Yes they are just Molex connectors and keyed uniquely so no worries. Just not sure if all harnesses are disconnect able without a game to look at.

The issue I have with either a regular pinball or a bingo ball in the Queen's Chamber, is that nowhere in the manual does it say, please insert the big ball into the Queen's Chamber. Unless the larger ball was shipped in a marked envelope stating this, or the unlikely possibility that the games shipped with the captive ball in the trough, but I strongly doubt that. Meh whatever. Put whatever ball you want in there I guess, it's your game

There should be a little hook for the back box key inside the cabinet right next to the front left leg bolt plate. It should be screwed into the plate itself.

Here's what all mine look like. It was more of a curved "hook" originally, but sometimes they are broken off.
IMG_1526 (002) (resized).JPG