What kind of sound are you looking for with this guitar? Rock? Blues? Funk? That will give us a good chance to figure out the best humbucker. I can't recommend BLs enough, so replacing the JB with a BL would certainly be my suggestion. You'll get a better sound, period! I like fuzzy's suggestions. I'd suggest them in the order of 610, L80, L90 if you want little distortion, mid distortion or a lot of distortion, respectively. Which ever way you go, you'll be happy that you did!

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