How do I route the sirius antenna cable antenna to the back of the car if I install it on the front dash? The part I am worried about is getting the wire down the backside of the dash.

 

There are plenty of ways to do that...you can go up the A-pillar and under the headliner. You can go down and inside the door seal. There are plenty of places where you can just press the wire between panels or a panel and a window. If you have an 02-04 the dash top is very easily removed with 4 screws and you can run wires directly inside.