The battery tray itself was made from white-finished aluminum. I then covered it with black adhesive vinyl. the white didn't look good :) The vinyl was scrap from a sign-making shop. I was charged only $3 for about 4 square feet worth which is plenty to easily cover 5-6 boxes... The padding inside is "Darice" brand "Foamies Sheets" sold at walmart for $0.47 per 9x12" sheet. It does not have an adhesive back but when matched with 3M Carpet Tape (very thin) it adheres quite well! The lower layer of foam is running lengthwise with holes cut for the button heads to sit in (as pictured above) while the top layer runs width wise and up the side walls to better cover the heads of the screws and protect the battery which is also pictured.
Here are the mounts we made for the box. Pretty simple. They raise the box just enough to clear the radius of the chassis edge and the side guard dirt deflector thing.
