Measure 90mm from the Nut towards the end of the headstock and mark the position of the scarf joint. I cut it using a scarf joint jig on the bandsaw. 
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I started by squaring up the neck blank. Planing one of the faces flat and smooth then squaring up both of the edges. I kept the blank wider than the widest part of the headstock….80mm. I allowed 200mm…   Read more»

@nolanrathkegmail-com You certainly can use it for fretboards. I’ve seen it used a couple of times. You might be lucky enough to not need to fill in any gaps but if you do I’d follow @nsj advice and use some…   Read more»

@dhawkes1gmail-com
I agree with robin. Just mark a new centre line on the fretboard and bring the sides in evenly to match your neck profile…… double check that your neck sizes and angle are correct. 
Good luck with it.
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