Camper trailer upgrade

Hi there folks,

Have been thinking of making some structural changes to my 7x4 CT trailer. It is only a "semi-off-road" so therefore not overly rigid in the chassis area. I have been studying the designs and reading the manufacturers blurbs, and wonder if I could strengthen up the whole thing by welding up a new chassis.

The current configuration is only angle iron welded to the floor and sides with some cross-menbers for support (probably your standard garden variety trailer) - the suspension is slipper springs (5 leaf) and I'm unsure of the load rating.

My idea is to weld up RHS (75x50, or thereabouts) to a design that will allow the current trailer body, minus the old suspension, to sit on top. It could be welded on all the way around, and have a new shackle and rebound leaf off-road suspension system (as offered by Alloy Industrial Springs) fitted, thereby lifting it somewhat (it is too low in my opinion anyway), and possibly extending the drawbar to 1800mm, giving me more room at the front for storage.

My Cousin is a qualified welder, and has built boat trailers etc... I really think that it would be cheaper than replacing the whole trailer?

Cheers! Paul.