Here is a cool video I found a while ago -- A.J. Foyt and Ray Harroun on "I've Got a Secret" in 1961. "Mr. X's" secret was that he had just won the '61 Indianapolis 500 a few weeks earlier. "Mr. Y's" secret was that he won the first Indianapolis 500 in 1911.
https://www.youtube.com/watch?v=Wo8E2bBpnRY