To be honest, apart from changing pick-ups, I'm a luddite with the soldering. Hence my initial inclination to drill the remainder of the metal bolt and put a pin in to secure the knob. That way would neatly avoid going near my weak spot of soldering and circuit boards.
Yeah, it can go back via Korg - I just need to get it to Milton Keynes. They'll then provide an estimate, etc. Certainly very helpful, but might leave me out of action for a while. No phone estimate from them, they need to see it all first.
I've tried JSS Audio, locally, so we'll see what they have to say.
I am unbelievably f***ed off with myself