I know this thread is a almost a year old but.... I have made a custom cooler for my son to fit in his Tacoma. I used the pink foam board from Home Depot and glued it together in the shape I wanted, then I cut and glued plywood siding (like what you put on a shed) and covered the seams with trim. Made a lid the same way with foam that fit into the top. Then I charred the grain with a blow torch, and put seven coats of spar varnish. Some SS hinges on the lid and I used wooden cleats for the handles. She looked great. Sorry I don't have a pic.