I've stripped the bike down to the point where the engine is ready to come out, I then blinked and lost my nerve after speaking to a few chaps that mentioned 'technically' how scary a bike gearbox was to rebuild.
So I'm taking it (in its disassembled state) to a bike mechanic chap that will strip it down and rebuild the gearbox and reassemble the bike, while giving it a good service.
My parts bill will be somewhere around £500. Labour will be somewhere around £200 or so. It's not particularly cheap, but since I got the bike for a steal, I don't mind so much ( And in the few months I've had her, I've chosen to keep her forever
)