2002 Impala, GM-SL

Installing an Autopage RS-725LCD in a 2002 Chev Impala. All connections are made, well, all that are required to get the auto-start working and that's what my primary concern is right now.

My question is this, on the GM-SL connector 1, the Blue wire says (-) input (ground-in), and shows a wire coming from the remote start/security system. My gut tells me that when grounded, then the GM-SL sends the proper pass-lock code to the ECM to allow the car to start. And I need to find a wire from the RS/alarm that is ground through starting.

If that's so, which wire should I use anyways? I installed an RS-620 yesterday and one of the wires could be programmed for this, but not on this unit. If I use the ignition 3 wire, then I think it should work, however I'm also thinking that the theft light on the dash will be on all the time then.

Question 2 is, and maybe my brain just isn't working full speed here, but on connection 2 of the GM-SL, white wire (-) output (door trigger). What? Output TO a door trigger? What's the point of this wire? (and yes likely totally obvious, but I just lost my mind)

thanks for your help!

Cool, thanks. Ended up using the ignition 3, and worked like a dream. No theft light even.

And finally clued myself in what the output trigger was for, duh, alarm! Still wish I could use the GM-SL for the door and overhead light though :( I still can't find where those things are located, exactly.