[Mike C]

I made mine out of 1/4" plywood and covered in black vinyl. It actually screwed to the mounting flanges in the back, and in the front I trimmed it where it slipped in behind the B-pillar flange that runs from the top of the bed rail to the floor. I drilled an over sized hole in the B-pillar piece, then pulled the panel out flush using a screw and trim washer. I have 6 1/2" coaxials mounted in them, and it works great. My first set lasted 12 years, and the current ones have been in there 8.