Thank you everyone for the helpful input. Franco, that is a great idea, however my woodworking skills and tool set are hardly the best and I think cutting a piece of mdf that thin would be a problem for me.
As for the "fill it in" option, I was and am still considering it, I was just worried about any putty gumming up the micro switches or falling into other places.
And bottom mounting would work as they sell extended shafts (insert joke) but i want to try and avoid nuts being on the play surface (insert 2nd joke?)
I am leaning towards just filling the gaps, and was wondering if anyone has done this.
Thank you all again.