98 corolla trunk trigger

I have a 98 Corolla LE with a Black Widow 3900 installed.  I wanted to hook up a trunk trigger to the alarm.  Where is the best place to find the trigger wire?  Do I have to run a wire all the way from the trunk light to the alarm?

FYI DIRECTWIRE™ WIRING INFORMATION - TOYOTA / COROLLA / 1998 / Security 12volts white   +   ignition harness Starter red   +   ignition harness Ignition BLACK/ white   +   ignition harness Power Lock blue/black   -   R side of fuse box, wht plug Notes: The lock wires are about 18 gauge. They will test only by operating the key in the passenger door lock cylinder, not the rocker switch on the door itself. Power Unlock GREEN / WHITE   -   R side of fuse box, wht plug Notes: The lock wires are about 18 gauge. They will test only by operating the key in the passenger door lock cylinder, not the rocker switch on the door itself. Lock Motor blue      drivers kick panel Unlock Motor red      drivers kick panel Disarm Defeat red      passengers kick panel Parking Lights+ green      bottom of fuse box Parking Lights- lt GREEN/ black      steering column Hazards           Turn Signal(L)           Turn Signal(R)           Door Trigger RED / white   -   instrument cluster or Notes: Also found at the fuse box. There are at least 5 RED / white wires at the fuse box, some will only pick up individual doors, meter them to find the one that will get all the doors, it will be the one that goes up to the instrument cluster, it is in a 12 pin plug on the back of the fusebox. For domelight supervision use one of the individual door triggers. Dome Supervision           Notes: Also found at the fuse box. There are at least 5 RED / white wires at the fuse box, some will only pick up individual doors, meter them to find the one that will get all the doors, it will be the one that goes up to the instrument cluster, it is in a 12 pin plug on the back of the fusebox. For domelight supervision use one of the individual door triggers. Trunk/Hatch Pin RED / white   -   light in trunk Notes: On vehicle with the factory alarm, can find these wires at the alarm module above the drivers kick panel. Hood Pin red   -   hood pin Notes: On vehicle with the factory alarm, can find these wires at the alarm module above the drivers kick panel. Trunk/Hatch Release           Power Sliding Door           Factory Alarm Arm arms with lock        Factory Alarm Disarm disarms with unlock        Disarm No Unlock           Tachometer yel/grn, RED / blu, gry, or wht   ac   any ignition coil Horn Trigger GREEN/ red   -   steering column Memory Seat 1           Memory Seat 2           Memory Seat 3           Interface Module: Category: Immobilizer Bypass Required: No Type: N/A Part #: N/A Notes: Smart Starter Kill Relays: Not Available        This wiring information is being provided free of charge on an "as is" basis, without any representation or warranty. It is your responsibility to verify any circuit before interfacing with it using a digital multimeter. Directed electronics, Inc. assumes no responsibility with regards to the accuracy or currency of this information. Proper installation in every case is and remains the responsibility of the installer. DEI assumes no liability or responsibility resulting from improper installation, even in reliance upon this information. Be careful whose advice you buy, but be patient with those who supply it.

Thanks for the info.  What gauge wire do I use to run from the trunk light to the alarm? 12 gauge?

An input wire, 18 gauge is plenty. Be careful whose advice you buy, but be patient with those who supply it.

Thanks....I appreciate the help!