LBJ certainly had the motive.
I still think the Mafia had the biggest motive. But I’m not saying they didn’t work with the CIA on this. LBJ was the slickest operator in Washington. If he was involved you will never find his fingerprints.
https://www.youtube.com/watch?v=_STRBD2_SX0
My issue with suspecting LBJ is that he simply dropped out of the Presidential race in 1968
If he was power-mad, you would think he would have tried to stay in the office.
Like today we all know the players and we all know the truth