They are not easy to change depending on if you have a 5.4 or 4.6 litter engine you either have wires or coil on plug ignition. They are located between the intake and valve cover on both sides of the engine you cannot see the plugs they are down in the head. If you are not mechanically inclined and have never done this type of job before Don't Do It. These engines will spit a plug out if you over torque a plug.