The G string on my bass is low enough at the nut to cause buzzing and harshness in the lower positions, and especially on the open G. (It's so low that I can't fit a business card under it.) The question is, should the nut be replaced (or raised, if there's even a way to do that) or should the fingerboard be reshaped? How much would something like that cost? Would this be considered major surgery or routine maintenance?