I was on the Viper web site. They have an alarm called CAN-BUS OEM system upgrade. But it seems to only have a shock sensor but it works with the factory key fob. It says it has one slot for an additional add on feature. I would like the battery back-up feature and for it to be wired into the interior lights for it to go off if a door was opened. But there's a 3902V and a 3903V, so not sure which one would work. More research needed.
http://www.viper.com/ShopViperProducts/ItemDetail.aspx?ItemCode=3902V
http://www.viper.com/ShopViperProducts/ItemDetail.aspx?ItemCode=3902V