i agree about getting an aftermarket alarm. i have a python(wish i got viper) with alarm and remote start. works really well. its got sensors so if someone fidgets with your doors for more than a few seconds then the alarm will go off... and trust me its annoying as hell. my buds tap my truck every once in a while just to set off the alarm because its pretty sensitive
The newest ones will even alert you if you are within a mile of your rig which is handy. i would go with one like this. it says retail 650$ but ive seen them for as low as 250$
http://www.viper.com/ShopViperProduc...ItemCode=5702V