I have worked on a lot of these. There were two versions. One with bally boards, the most common. And another with older SS Stern boards that came with a unique backglass. Basically identical in design as bally and Stern boards were interchangeable of that vintage.

I don’t think I have much documentation. But they work exactly like an old bally pinball. You can swap boards and displays with anything old bally. Power supply, displays, driver board, and CPU are right out of a pinball l.

Some of these even used a sound board. I always thought it was weird to put a sound board on a bowler like this.
I am attaching a picture of one I worked on that used bally -17 CPU and had the backglass with the kit.
I have a Stern version over in storage. Will get into it one of these days.

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