if it was me, I'd sand down the back of the neck and do a wax/oil finish (like Tru Oil, or Howards Feed & Wax).
maple fretboard is more challenging, you might just make it more stained in the process. This is the main reason people do no try to clean a maple board. I have nothing to recommend for the maple fretboard.
maple fretboard is more challenging, you might just make it more stained in the process. This is the main reason people do no try to clean a maple board. I have nothing to recommend for the maple fretboard.