Skull podium topper is made out of 10mm coro
It has 5 1" holes for push buttons (or order without holes for custom spacing)
It is 16" wide by 18" tall
Link to push Buttons.
EG STARTS 5X Arcade Buttons 60mm Dome 2.36 inch LED Push Button with Micro Switch for Arcade Machine Video Games Console
Link to controller
Plans for what I used to build are in pics below.