Using your wiring diagram, find the wire responsible for activating the starter solenoid and install a switch as far from the ignition as possible in that circuit (you don't want the potential ...

John Paul, AAA Northeast's Car Doctor, answers a question from a reader who ran into trouble after installing a new ignition switch. The post Did swapping an ignition switch do more harm than good?

So remember, unless you have on aftermarket ignition, the positive side of the coil goes to the ignition switch (usually through a ballast resistor or resistor wire), and the negative side goes to ...