OK, this is probably a stupid idea, and I'm sure you'll all tell me why, but has anyone ever thought of making a big 4 wheeler sankey trailer by welding two normal ones together? My idea is you would cut one just beind the back spring hanger, the other in front of the front one, and join them together. Given the seperate chassis/body, and the fact that everything is straight lines, it shouldn't be too technically difficult. You would end up with a decent sized trailer you could put at least a ton into, probably more. It would also only cost about 300 quid plus some effort.
The only potential issue I can think of it that once it's a 4 wheeler you have to have your NATO hitch at just the right level for the trailer, as you can't get away with having it a bit off level.
Hmmmmmm.
Paul