Custom Rear Side Panels

[FoxHound]

Been trying to find the thread for this, pretty sure I've seen it before but not having luck...at any rate I know no one on here wants to pass up an opportunity to show off their truck

I'm putting in a stereo system in my k5 and want to mount the speakers within some custom made side panels in the bed. There's no way I'm paying for the china-made LMC ones, especially when I know I can make them way cheaper. Anyway I'd like to see some pics of what y'all have made. I'm leaning towards making them out of plywood and upholstery but by all means post up anything you've got, always down for new ideas. I've seen some pretty cool diamond plate aluminum ones. Thanks