456g Help 03 silverado DEI

Looking for the Data Bus Imput for a 2003 silverado to hook to the Data Bus Output on a 456g. Also need the (-) door trigger imput of the truck to hook to (-) door trigger output of the same 456g. I know that I could use different mods now, but I'm this far and don't want to change everything. Thanks in advance.

The unit i have does not have a alarm. the 456g has these wires I can explane all but those two and i understand your explanation of the violet wire. dont understand the door trigger wire. let me know. thanks

456g

red                 power input      red ignition harness

black             chassis ground           ground screw

grey/black        dome light input        grey/black black plug pin e at bcm

RED / white           non keyless programing   not used

blue                    (-) status input   (-) keyless programming     orange on remote start ground when running (-)

ORANGE / white                   not used

orange black                  not used

green                               ????????    (-) door trigger output

violet                                 ?????????  data bus output      are you saying violet at obdc plug under dash

why dont they make it easy  i appreciate your help and quick response