I have an '06 mega cab 1500 SLT. I am upgrading the stereo to the factory REC navigation unit and adding the Mopar Sirius receiver. The new receiver has come in and it has very short leads on the antenna, only six inches or so. I assume I need the wiring to take it to the receiver which mounts near the head unit. My question: is there wiring already in place from the factory that I can use for this, or will I have to buy my own and run it? Even though the truck did not come Sirius ready, I wanted to know if they came pre wired. Thanks for your help.