3G alternator no charge light wiring

[51504bat]

I'm installing a 3G alternator on the 302 I'm putting in my '54 Ranch Wagon. I wired it like the 2 attached diagrams show and it charges fine but I can't figure out the idiot light or no charge light as Ford refers to it as. My guess is that the light assembly isn't just a typical light socket with a hot and a ground. Can anyone shed some light on this? (no pun intended) Thanks.