I'm not sure if I remember it correctly, cause it was on my 91. I didn't use the aftermarket harness, instead I made a custom one myself.
The head unit was a Pioneer. The ANT wire is the #7 in that picture (the connector is below the passenger seat) BTW, it's actually connect to the connector behind the stock head unit (which I don't remember which line) You can use a meter to test the continuity of these wires.
One thing, the antenna relay is connected to the stock amp and the amp must be turned on, otherwise the antenna will not work. This is the P-L wire (#1) in the picture above. I hook it up with the "remote amp wire" from my Pioneer unit.