you can play the flexwatt and then set a piece of plexie on tope and if you want to put some form of spacers between the two you can in the form of some washers from a hardware store ( just hot glue them to the plexie) ( get a stainless steel kind . and a lot of them you will want spares as you lose them or drop them during assembly.
also you can make a sliding glass front if you want ( it not hard ) just cut a groove in the front framing and I got a metal U shape metal ( at Lowes) and set it in the channel and set the glass to slide in that. with the2 pieces overlapping enough not to get stuck. ( also put the groove in the side frame parts to make the glass unable to be pushed on by the snake. ( just remember to attach some kind of handle to grab on the glass lol it hard to just slide open with out a handle )