The quarter boxes will need a 1″ hole cut, but it would be easier to wait ’til they’re already put together. They will not need holes on the center wall of the box. Watch where you’re nailing on the quarters–don’t put a nail right through where you want to drill! If you’re using a router, specifically the round-over bit, wait to drill that hole until after you’ve routed–otherwise you get these funky divots when you route.