Not to be picky but for clarity what material are you using? You mention plexiglass and polycarbonate which are 2 different things. Polycarbonate is better known as Lexan, and plexiglass is a trade name of cast acrylic. Plexiglass will thermoform but is more brittle than polycarbonate. If you try to drill holes in plexiglass without being extremely careful it will crack and that crack spreads very easily/quickly where I see Lexan (polycarbonate) being the better choice for this application. That being said I believe that Lexan is more expensive than plexiglass.
I do like what you made and I'm glad you posted so much information and pictures showing us how to mimic it. I'm just trying to help anyone who may be following your instructions so they know what material would work best.
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