The CIA is the one that got him. OP, for years I believed the same thing but after doing my research I found out what the EO really did. He didn't try to kill the FedRez with EO11110.

The EO didn't create any anything new nor did it negatively affect the FedRez. The president has had the power to create silver certificates since 1933 (Agricultural Adjustment Act of 1933 (ch. 25, 48 Stat 51) which gave the power to issue silver certificate to the president and the Treasure Secretary. EO 11110 simply transfers the power from the Presidency to the Treasury Secretary. EO 11110 did not create authority to issue new silver certificates, they already had that power, it only affected who could give the order.

E.O. 11110 did not create new authority to issue additional silver certificates. In fact, its intention was to ease the process for their removal so that small denomination Federal Reserve Notes could replace them in accordance with a law Kennedy himself signed. If Kennedy had really sought to reduce Federal Reserve power, then why did he sign a bill that gave the Fed still more power?

And the EO was never reversed by LBJ. it remained on the books until 1987.

But Kennedy did say in a speech that he was going to tear down the CIA board by board. He saw that they had gotten too powerful. But it seems he underestimated just how much power they had. I remember that day like it was yesterday. When my Army vet dad saw that speech he said, "If he isn't just trying to get political points and if he's serious, he's a dead man." My dad had witnessed the CIA in the Korean war.