I have this funny nook in my woodshop which perfectly fits the XL, decided to just use the space to act as enclosure walls which allowed me to hang some large sound dampening panels (treated with Fireguard). For the front doors I used Poplar for the frame, inset some large plexi sheets along a dado cut, and made a very easy/quick open latch system with a rare-earth magnet and a metal washer epoxied into the frame. This latches closed, but opens immediately if I need to jump in there. The plexi doors reflect a good amount of sound, I was surprised at how effective they are.
One unplanned added benefit to this latch system is if the dust boot comes all the way to the front on the Y axis and hits the enclosure doors they just pop open a little bit - no lost steps.
Thought this might give some ideas to anyone thinking about enclosure options