After looking at website still kinda unsure about what product of there's that you have. Is it a extruded clip together aluminum frame or some sort of angle pieces ? Either way I would use plexi over glass only because plexi in easier to use and cut although for me I like glass better(clearer). Make sure to seal all gaps inside with aquarium grade silicone it will seal and add strength to the box. Please post pic when done. Good luck.