Sorry, let me clarify.
I'm using real Williams pinball parts as feedback devices for a virtual pinball machine. My plan is to build a "playfield" with pop bumpers, sling shots, flippers, a knocker, and a shaker motor underneath the main display.
So I'm looking for information as to the best way to physically mount these units. Obviously wood screws will be inserted into the mounting brackets, but I'm not entirely confident about the hole sizes. I can just guess, but figured I'd ask first. Unfortunately since the assemblies are sold as replacement units, the supplier just assumes the purchaser will be mounting them on an already prepared playfield.
Fortunately I have come to understand a Williams pop bumper utilizes three overlapping holes in the playfield. But I don't know the correct dimensions of that cutout.
Make sense?