After a little research, I figured out that I left a ground wire off. I know it connects to the top of the case right behind the fan housing, but I don't remember where the other end goes. I'm guessing it goes somewhere near the alternator, but where?

It connects to the ground connector on the back of the alternator.

Click to view attachment

Guess the shroud needs to come back off...

Right after the Seahawk game

Click to view attachment

Which is the ground?

In the picture of my alt. (75 2.7) the red wire is connected to the connector marked B+,
The brown wires(ground) is connected to connector marked D-, the blue wire is connected to the bottom unmarked connector.

Hope this helps.