Don't do it! If you have to ask the question you don't have the expertise to do a perfect job; unless, of course, you don't care about that or about resale. My first pair of Stax f-81's had been painted in piano-black by the previous owner, and I must say that the end result, while not exactly perfect was pretty good. And DON'T USE DUCT TAPE! You'll never get the tape residue off without ruining the finish.