I've got a 2008 DC with the factory towing package, and I'm planning to purchase a travel trailer in the coming weeks. I've got a trailer brake pigtail in my glovebox which I plan to use for the installation. I've read several threads about the installation of a brake controller, and none of them indicate whether or not I'll need to purchase/install any additional fuses or relays. Are all the necessary fuses & relays already installed by Toyota, since I've got the factory towing package? In other words, I can immediately hook up to a trailer, adjust (dial in) the controller, and start towing?