So I have a Thumb BO (a 2006 or 07, can't recall the exact year), and I was wondering the proper cleaning materials to keep the fretboard in good shape. I use the Warwick wax on the body and the back of the fretboard, but I do not know what to use on the fretboard. I have heard mixed reviews about using lemon oil or lemon juice for it. Are there any products designed for this exercise? Any help would be greatly appreciated.