I had an Eight Ball backglass once that was too small. Just enough height wise that we thought it might fall out of the cabinet, so we had to add an extra piece of trim on the top channel so it would have something to rest against.
I bought it as a repro but was thinking maybe it was out of some run of Eight Ball that was slightly smaller or something. Strangest thing I ever saw, it was maybe 3/8" short. Really nice silk screened piece though that looked perfect.
Found a picture... if you look close you can see the extra piece we had to add at the top. You can see the width wasn't quite right either, I guess the plastic trim would have helped though.
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