i iam getting ready to order a fully loaded o6 3500 swd quad with auto. does anyone know if the exhaust brake has to be ordered when you order the truck ,or can i order it from the parts dept. after it comes in. i can get a good price through parts since iam good friends with the parts mgr. i was wondering if the factory does something special to prep the truck for the e-brake. thanks a lot, joe .