Take the single lead off the starter, get a multimeter and back probe (simply stick the prong that is "positive" in the connector) and put the negative probe on something to ground it, have someone turn the key, if the multimeter reads 12 volts the ignition lead is good, if it reads nothing the circuit is open somewhere from the ignition switch to the starter solenoid. You can also check the clutch relay and manually press in the clutch interlock switch (this is what the clutch presses when you press down on it before you turn the key). Make sure that the ground coming off the battery is on the chassis in a clean spot (this is what grounds the engine and transmission which is what the starter presses on and grounds the starter to complete the circuit) I had a bad negative cable coming off the batter and had to replace it. If you replace it make sure you do it right -- the negative cable goes off the batter and onto the chassis and/or engine block NOT THE STARTER ITSELF!