Headstock Location pin:

the pin that locates the headstock to the bed
I measaured the headstock alignment pin holes in the bed of my heavy 10 and the hole is ~ .312" while the headstock hole is .350"
Alec Ryals 
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The locating pin does not have to be a precision fit in the bed and the headstock. It's purpose is simply to keep the headstock in alignment with the gears on the banjo and the gearbox -- this saves you a few minutes of assembly time.
Alan
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