Vehicle Turrets?

I would like to add turrets to my vehicles, so when someone mounts the vehicle (the passenger) they control a turret on the vehicle (like a machine gun). I have searched the forum and didnt find anything that helped. I have looked at the Turret & AITurret classes, Version 1.20" resource and asked "Master Treb" if the resource can support vehicle turrets and he said "I don't know about mounted onto vehicles but I believe there are seperate resources detailing how to do that." So could someone help me add turrets to my vehicles?

Thanks.