Well had a bit more of a dig with mixed feelings and findings,
That vertical seam that was full of sn*t well its all bathroom silicone, clear as well.lol so raked it out quickly and this is what was behind it

good int it, will only need gritblasting and then normal prepping, could be lulled into sometyhing here

now the seam is a bit ugly but all in the right place but

there is a hole in the arch too, the whole of this panal well most of it is filled, looks to have been bumped maybe off road who knows, but it has been done by someone who knows how to fill , I think a template was made up to guide the cutter/grinder, then when done the correct grey seam sealer was used , but at some later stage the bath silicone was applied over the top and the van had the bottom half painted.
bottom gone

this piece apears to have been added as the join is at the top of the swage and very nicly done, there is only a slight bump which would be hidden by the rubber arch.

as there is a seam at the rear !
I may have to remove the cover securing edge as there is rust at the rear of it theat the blaster will not touch

but easy enough to do and respot.
So its removal of the rear furniture and get to the inside of the rear wings andd arches and see just whats been going on
mike