You are correc sir. This never actually went forward. And it ONLY got as far as ALL of the Joint Chiefs of Staff signing their approval on it and submitting it to the Secretary of Defense for his approval, which he may have given. McNamara would likely have approved a plan like that. It was only Kennedy that put a stop to it, and that could be one of, if not the reason that they had him assassinated.
No, the Kennedy death was the result of a mafia hit. JFK and his brother were trying to bring the heroine trade out of Cuba to a stop and certain mobsters, Traficanni, Hoffa, etc ordered the job. A lawyer here in Tampa who defended mobsters in the 60-70s who is very famous said as much and I know someone who knew him and confirmed the story.