so, some progress.
simon stripped the floor and sides off as they were either rotted, or on their way. the chassis was in good nick, but he future proofed it by reinforcing it with extra struts. (25mm box ) section

the floor was replaced with 4mm chequer plate, siliconed and tech screwed all round.

next, the carry box for three jerry cans to carry pump diesel in

again made from 25mm box and 7 inches deep. will have high density foam lining to stop rattle and lateral strap to keep them in place.

plenty of space to clear the lid.

and some new sides all round, with the alloy caps and runners replaced.

off to collect it tomorrow, then will sort out the wiring and a few other bits to make it exactly what i want.
more pics soon.