I have a buddy that gets stars to sign guitars. He's been doing it for years. He uses a certain type of marker that rubs off with just a little elbow grease. He'll photograph the autograph on the guitar (kind of artsy) and wipe it clean for the next "star". Collects 8x10 glossies of famous signatures on guitars, without the permanency.
Killer guitar! They ain't makin' them anymore...