Curiosity got the better of me..
a few places where I can get the edge of a finger in between the tube/floor/transom seam.
The floor has had glue sprayed into the valves and inflated to pressure to force 'glue' (he said some kind of pvc glue) into the leaking areas along with external patches at the rear end
All three tube valves have leaking inner spring seals (not sure if what they're called) but stop leaking when the outer valve is closed.. taking off the outer cap you can bear a slow hiss
Brackets for launching wheels are present but have been screwed to the transom and are rusting/rusted. Would need to be drilled out and SS bolts used
Told him I'd have a think - buying some time until folk that know more about these floors than me happen past this thread [emoji2]
Would the spray in glue cause problems? I'd guess it would coat all surfaces inside the floor..