Fitting a Trackball and spinner on that? Nah
I think your better off building a new panel. I hope you used latch clamps or some sort of hardware like that for your CP insted of screws or glue so it's easy to swap.
Or better yet, maybe start a whole new bartop project for trackball/spinner games.
I mean why not? A 4' sheet of ply or MDF, a small LCD monitor and computer off craigslist maybe, and a few other tiny compnents. Shouldn't run you up too much huh?