[chevytruckluver]

Hi guys, my son just bought a 79 K5 Blazer. Its got a new battery and a new alternator. When he bought it and drove it home today he parked it and came out later to find it would not start. He jumped it off and it started right up. He has 12 volts at the post on the back of the alternator. The plug on the side I'm not sure what he has there. I think that the brown wire should be hot when the key is on? I would love it if someone could point me to a wiring diagram.
Thanks in advance