okay an update,
thanks for all your help I got a coolant distributer manifold from VW £34 in total after VAT and me collecting it on my way home. that was £27 cheaper than JK and £16 cheaper than second hand, I think even brickwerks are looking to sell them for £40(ish), make sure you always shop around when you need a new part
fitted the part, bled the water system a few times I may do some more tomorrow just in case there is a tiny bit left
even treated camper to a new set of battery terminals and replaced all the ends joining the battery to connect to the new terminals and changed the "falling to pieces" ring from alternator to starter hopefully that will sort my intermitant charging issues out a bit (and it looks neat and tidy now when I look at the top of the battery), put in some fuel and embarrased my daughter picking her and her friend up from the station, the last run 10 miles around the block engine idling whilst I moved all the stuff back into the back and 25 minute round trip was over an hour, I assume I would have noticed a leak by now as the system would have been well upto pressure.
camping then in a couple of weeks

Dylan = C Reg 1986 T25 1900 Water Cooled..