Made these door panels out of plastic(Cardboard looking). Just traced out the panel...Lay your cloth or what ever your going to use. Leave a extra 2 inches hang over...spray uphostery(Glue) over the top panel. place the materal on top. then flip it over and glue the flaps over on the back side. I used my soldering gun to make small holes so the sheet metal screws won't pull on the Cloth/materal.

Total cost $5.00 for the Auto uphostery glue.
Plastic Panels(Cardboard looking)-Free From work.
Camo- Free already had laying around.
Time- about a hour per door. Fab & Installed.