05 chrysler 300 oem alarm disarm

Iam going to install a Black Widow alarm on a 2005 Chrysler 300.This vehicle has a factory alarm and just because the customer has only one key/remote,he wants an aftermarket alarm with two remotes. Iam curious about the oem alarm disarm wire as the wiring schematics i have gone thru state passively arms with oem remotes and there is no mention of a disarm wire. Would adding aftermarked alarm and keyless entry take care of the factory alarm going off when unlocked or is there a factory alarm disarm wire which has to be found and used for this application. Thanks for any info.

just leave the car unlocked with the factory remote and use aftermarket remote only. if he uses the factory to lock the alarm will go off then.

The only other way would be to install an immobiizer bypass module, with a spare key inside, and have the Black Widow trigger the bypass module, and power up the ignition at the same time.

Would using a bypass module (which has door lock wires,alarm disarm)work as i will not be doing the auto start,just the alarm and the data link wire so i do not have to do the transponder part of the bypass.