Oct 15, 2014 - 01:18 PM
I would recommend to test it first. It is usually ok to stain or paint after treatment, but for a fine finish such as on a guitar, there could be come differences where the stain penetrates and doesn't penetrate. I really can't give you a good answer as I have never been asked this before. In 25 years of using it, I have never had a complaint either.