ClassicCar

If this is a two wire internally regulated 6V Pos ground alternator, then the simpler way to wire it is to run the field wire from the alternator to the AMP light. Next move the wire that runs from the AMP light to the IGN terminal on the ignition switch to the "ACC" (accessory) terminal of the ignition switch. This will prevent the alternator from feeding current back to the coil after shutting ignition switch off. If you leave the field wire to AMP light hooked to the IGN terminal without a one way diode, the engine will most likely run on, albeit roughly after switching the ignition off, and the AMP light will glow. If you use a diode, then you could leave that AMP light wire on the IGN terminal as original. The BAT wire from alternator should go to the battery side big stud on the starter solenoid, with a 3/8" ring terminal. Horn relay wire can go to the front, BAT side terminal of the Starter solenoid terminal, same as the BAT wire from the alternator.