Priority Unlock Wiring (Driver's Door)

Usually you must have a system capable of priority unlock. It will have two seperate unlock outputs. The systems we use at my work require you to hold the unlock button for 3 seconds for trunk release. If the customer wants priority unlock, we take the unlock wire and hook it to the drivers door unlock wire (thru a relay) and then we connect the trunk release to the vehicle unlock wire. Customer presses unlock 1 time and drivers door unlocks. If they hold unlock it will do the drivers door first and then 2 seconds later will do the other doors.Not familiar with Astrostart except the ones I have torn out of customers cars, so I'm not sure how you could do it.

Thank you JW