spokeshave, rasp and sand paper
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Timpson Guitars and TDM Pickups rock ;D

I make guitars and pickups. I also make sh*t that'll blow you the f*k up as well as things that will rebuild you - I have the technology
You could probably do it pretty easy with a badass belt sander. Just start with really rough paper and work down to super fine towards the end.
None are more hopelessly enslaved than those who falsely believe they are free.