[kheiret]

the best way to fish the antenna cable thru the firewall is to use the rubber grommet on the passenger side - just cut the tip off with scissors. if you compare it with the one on the driver's side you'll see (at least on my DC) that they both have places to run a cable and the one on the driver's side already has one running thru it. Also, you can run the antenna cable down the rubber strip on the passenger side and then under the rubber strip on that side of the windshield. I used 2 credit cards held together with one slightly lower than the other so that the lower one opened the edge of the weatherstrip and the other pushed the cable under it. It worked very smoothly and I was able to run the cable in about 5 minutes total. I did have to lube the cable end to get it thru the grommet hole with a little silicone spray since it's bigger than the hole - this was a sirius antenna, the XM antenna might go thru more easily.