Is there ever a valid reason to remove a serial number from a bass? I doubt it— The only reasons I can think of to do so are both dishonest: 1— to mask that the bass has been stolen, or 2 — To deceive a buyer into believing it is a different model from what it actually is. This is a prime example of the latter. You could attach the swing tag to a piece of cheese, but it won't turn it into a roadworn Fender bass.