The Luthier guy turned out to be not viable, he was really a vintage guitar restorer/repairer, and wanted about £600 just to look at it. However, he did give me a few ideas of what to do. He said that trying to get the glue unstuck to get the neck out would be a bit of a problem and might result in some damage. So in the end I have utilised a couple of 90 degree brackets. and screwed them into the top of the neck fitting where it slots into the body and then into the side of the cavity, which is into the main guitar body, one on each side. Sorry forgot to take any pictures - was in to much haste to rectify the problem ! So, in theory this should stop the neck moving in any direction now. I then re did the shielding over the two brackets - so still no buzzing etc. Probably sounds a bit unconventional but hopefully it will work, if not it will be going to plan B - neck plate. We'll see.