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The neck can be finished with a coat or two of Watco Danish Oil- natural tone, or similar type self-drying oil. The fingerboard can be dyed black with aniline dye.. Fibbings or Tandy leather makes a suitable dye. However, if the board is naturally red-colored (rosewood) or striped ebony, you can also put a coat of Danish Oil on the board and skip the black dye.