So this is another one of the the Jigs I made so I could radius the fret-boards and do compounds as well has some adjustment screws at either side once you set it flat on the bed,It worked OK as you are really taking just a lick off the edges .
One of the things you do I suppose is a blank electric neck with fret board attached and then shape later I never got that far just did a couple of fret boards with a you bute double sided tape and then a thin blade to peel it off

Seeing as I had the sander and some scrap metal I thought I would give it a go ( in the midst of res-erecting all the old jigs I made) all good fun ,John.

John ,of way too many things to do.