Interesting little snippet from the Rolling Stone interview of E. Howard Hunt...

E. Howard scribbled the initials "LBJ," standing for Kennedy's ambitious vice president, Lyndon Johnson. Under "LBJ," connected by a line, he wrote the name Cord Meyer. Meyer was a CIA agent whose wife had an affair with JFK; later she was murdered, a case that's never been solved. Next his father connected to Meyer's name the name Bill Harvey, another CIA agent; also connected to Meyer's name was the name David Morales, yet another CIA man and a well-known, particularly vicious black-op specialist. And then his father connected to Morales' name, with a line, the framed words "French Gunman Grassy Knoll."

So there it was, according to E. Howard Hunt. LBJ had Kennedy killed. It had long been speculated upon. But now E. Howard was saying that's the way it was. And that Lee Harvey Oswald wasn't the only shooter in Dallas. There was also, on the grassy knoll, a French gunman, presumably the Corsican Mafia assassin Lucien Sarti, who has figured prominently in other assassination theories.

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I guess E. Howard Hunt would have been in a position to know and it sounds credible but I guess we won't really know for sure until the Warren Comission reports are unsealed in 2023.