Gday Bruce -
Alternators...the bane of my existence.
Finally sorfted mine out tonight. i have a L76 but am using a LS1 alternator - these are not the same. The LS1 has the battery terminal (the large post) and a L and S terminal.
The later L76\l98 alternator has a L and F terminal.
I was feeding the gen F output from the ecu to the S terminal on the alternator. After a bit of searching tonight figured these arent the same - the S from the alt needs to go to 12v (I guess is this is the one you have going to the battery also - my understanding is that it should pick up the 12v elsewhere in the loom though as a measure of average voltage through the sytem) and the other is the L terminal which is the charge light. This need to go to the battery light on your dash, with +12v on the other side of the light. This circuit also supplies startup current to the alternator to ignite it to start charging.
Hope that helps and I hope Im right - but thats is what works for me.
Cheers,
Andrew.
(Justin beat me to it
- I waffled, but we are saying the same thing)