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I bought a boutique guitar, used from Guitar Center. I really want to like this guitar. I just got it a couple of days ago. Looking forward to doing a setup. The neck is straight. I went to add some relief and found that the wood around the truss rod keeps the 4mm hex key from engaging. Any suggestions on how to hog out enough wood to get access? I was thinking of superglueing some 180 sand paper to a 4.5 mm hex key and sanding the area until I can get the 4 mm key in.

The truss rod access area on the head stock is in the style of a Reverend not scooped like a fender or gibson.

I tried taking pics but it's really tough to get the correct angle.

Thanks for reading.