Here's a weird one. The song "Wipeout" by the Surfaris has apparently been the subject of more false claims than almost any song ever. Hundreds of people claim to have played guitar on it. In fact one repair guy even made that claim once to the real guitarist's wife.

http://www.buriedlede.com/journalism/wipeout.html

The strangest one though is John Mason, former head of the Nevada Republican party who's lobby for ambassadorship ended in embarrassment when he publicly laid claim to having been the Surfari's guitarist. Subsequent research reveals that not only was his claim false but also that the closest he had ever come to being in the Surfaris was when he got ran out of town by an angry club owner here in Calgary for fraudulently booking himself as The Surfaris. Surreal. That's definitely one of the odder stories I've ever heard.

http://www.polarity1.com/pcrr2.html

This may bear some relevance on a gig I heard about from Edmonton. A friend told me a band claiming to be the Surfaris got booed off stage there in 1963. Apparently they were so bad that the crowd got violent...