These tops look like they might be the way to go. I am going to leave one hollow as stock .the other top I intend to fill with expanda foam .I imagine fill with foam will be superior as in coolers . However time will tell also I will have to see how the sun affects it. As for out of the box toughness I can stand on it and I am not a small person by any measure. Lastly this had the best price of the places I checked. I checked about ten sites.
Will I buy more I image as ì expand I will.
