If you want an idiot light, just put one inline between the ignition switch and the white wire of the 2-wire plug that connects to one of the two terminals on the perimeter of the 10-SI alternator. The red wire gets jumpered to the big output terminal at the back of the housing. If you don't want to buy the factory plug, just use #12 wire and flat female terminals. Looking at the back of the alternator, the constant 12V wire attaches to the right terminal, and the idiot light ground attaches to the left one. That wire is optional- - - - -if you're using an ammeter instead of an idiot light, just leave that terminal open. The diode is needed if you choose to attach an "exciter" wire from the ignition switch to the left terminal to prevent a backfeed to the ignition system that keeps the engine running when the ignition is turned off.
Jerry
