It looks like I need to go pick a sheet of plywood and some rigid insulation. My trailer is not long enough and just a hair too narrow to support a 4x8 sheet, so I need some supports. Last time I used a couple of 2x4s, but they moved around and the wood went wonky. This time I took some scraps and cut slots in them so the scraps would lock onto the sides of the trailer. Observe!
I intend to trim the length just a little bit and then they will be ready to use!