avital 4100 and window rollup

Got a guy with an 04 grand am. We installed the keyless entry and trunk release. Now he wants to add a window roll up to this vehicle. My question is this, how would i do this? The remote start system only has the trunk release option output, nothing else for adding an additional item or channel. How would I install the roll up module? He just wants it to roll up when the door locks.

Seeing that you're installing an Avital get a 529T from DEI who also manufactures the Avital. This is a window rollup module which will roll up two windows. It can be activated by connecting to the doorlock output of the Avital.