Well like on my $15 window mod i used brass strips i picked up at a hardware store I put the glass on the inside of the case then ran the bolts you see through the brass and the case then used clips on the inside, attached to the bolts, to hold the glass in place. One thing you may be able to use is rubber hose, find some without writing on it, split it end to end and glue in in place, never done it but it may work.