2002 Avalanche remote start trigger wire?

I have reviewed several different list showing the Avalanche lock and unlock buttons....I'm installing a remote start and cannot not determine what i should use. The vehicle has a factory keyless system already in it. I'm using the factory remotes and the remote start unit is programmable for this. but which wire should i go for., and can this be done without wiring a relay. I have thought about the gray wire in kick panel but there are 3?, and light blue at bcm...Suggestions would be greatly appreciated. thanks so much.

what unit are  you using? are you trying to add the starter to the factory keyless entry system? if so most tie into the lock and unlock wires. pressing l, ul, l again should start the car. maybe i read the post wrong. anyways could you fill in the balnks for me.

If you use a DEI piece use the white unlock wire in the brown plug at the bcm. You will need a relay. 85 and 87 ground 86 12v and 30 neg activation of starter( on DEI WHITE/ blue)  Hit the unlock button twice and VaroooommmmmJohn J. DiStefano Jr.