Biggest mob documentary bullshitter for is Richard "The Iceman" Kuklinski. I was always waiting for him to claim he was the second shooter in Dallas, when President Kennedy was assassinated, or claiming he killed Hitler in 45'. He was so full of shit.
Kuklinski was so full of shit, it was embarrassing. By the time he claimed that he did the hit on Carmine Galante, I threw up from laughing.