Thanks for that link, I'm thinking that if I can get something mostly done, and then sort out the axles, or whatever, then I'll have something I can use rather than planning the 'best of the best' but never getting it finished.
This thing here on TM with a trailer frame attached would be half way there, or something similar. There is probably an outfit around that could make up a freezer panel box and I can do the doors and windows
For added weird ideas, I thought about having the trailer with some sort of steel things in each corner like 'dozer ripper points, that slide up and down, put a winch in the front of the trailer (cos its already got a battery on it).
So when you get stuck, the crew pushes the trailer back 10m or so, jack it up, put the ripper points fully down, and start winching, trailer acts like a giant anchor plate with self setting anchor pins.
For use in braided rivers when you only have a single veh.
Anyway I thought it was a good idea!, almost as good as crowbar-ing in a hole, dropping a chain in and then pouring quick set concrete, winch out 1/2hr later. Haven't actually done that one, but I'd like to.