The #2 "sense" terminal has NOTHING to do with a diode or indicator lamp. It is simply jumpered to the alternator's large output stud, or for more accurate battery voltage sending, connected to the battery cable at the starter switch or solenoid. It can remain powered up at all times.
The #1 terminal is the "excite" terminal, and that is the one that gets connected to the "load" side of the ignition switch, though and indicator lamp or a diode.