First, we must study the foundations of the U.S. government and must find a weak spot within the laws/rules. Secondly, we must build our power within the government. Finally, use these loopholes and become supreme leader. That's the simple bases.
So basically you haven't thought the details out-
Yes first lets take down the military forces though and other places where US special forces are located.
No, we must establish laws that make our power and rule unquestionable. they cannot refuse or question our authority. we might need them. if not, then yes. we will figure out a way to make the FBI no more.