I don't have time or interest for a project like that right now.
The more I look, the more trailers I find that will work. There's one up in Holland I was about ready to buy, but the guy sold it. I need to get some better measurements on my truck, but I think I can get away with a standard 8.5 x 32 race trailer with 12" extra height. Might need to get 18" extra height, not sure yet. If I can't find a used one that will work be February or so, I'll have a new one custom built for me.