I am getting ready to sell my MIBS and it reminded me of something I forgot.
I created some 3D printed bonus ball back glass protectors.

It will work on MIBS and looks like maybe Bowling Queen. I don't know old Gottlieb EM machines, so not sure if there is others with similar mechanical back box.

I have them in 3 separate panels that attach to the bottom of the trough with magnets.
I know some people have just done sheets of various materials attached to the wood surrounding the area. On my machine someone had done paper taped to the back glass. I wanted something a little more elegant and easy to remove or adjust.

They may stick up a little high for some peoples taste. But they could be scaled at print time to make them shorter if desired.

I have posted the 3D files to Thingiverse. I also have some pictures of it there. Free to download and print on your own or have someone else print them for you. http://www.thingiverse.com/thing:763998

Hopefully these will be useful for someone else or inspire someone to make some in another way for their machine.

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