Here's what we do with our boxes, my designs, CNC cut everything. High quality birch purchased from wood supplier. We get Lexan by the 4x8 sheet, it's hundreds of dollars per sheet, depending on thickness. We use 3/4" and 1". We do carpets, stains, bed lining, paint, paints schemes, wood inlays with carpet, wood overlays wrapped in carpet, painted inlays with carpeted box, it's really whatever.
My builder's recent boxes:
I remember designing this one, it was fun:
My Explorer before I got really sick:
Some of our older boxes, some I built, some my builder built, most we did together, I did the wood part, he did the finishing stuff, paint, carpet, etc.
I made this octo port box, I made the port for it, they aren't hard to make. Centering the port in the box is another story.
Back in the day, tuning my buddy's 4 Q Power 12's in his Blazer. This thing was loud, also had a built drag motor (carb'd 350 ~425hp+ @ ~ 7000 RPM) and 3 speed in it LOL.