OK ............... we are back in business.
I have modified the rear deck to prevent water ingress. This was done by fitting a raised edge around the rear deck with angle plastic (from B&Q). The internal structure braces were raised to allow the new section to sit flat across and form a rigid base. Note the concrete block doing the job overnight.
The removable green deck with the fittings was fitted with the matching angle plastic to sit over the raised deck. The whole lot was Epoxied with a slow cure epoxy mix. (the commercial stuff, real boats are made with)
This was allowed two days to dry and then was painted green to match up nice with the boat.
When I do the waterfall test, I will know if I require an insulating pad around the internal rim or not.
Here are a few pictures of the modification.
Cheers...Ken