Sorry about the flash, it's nighttime. Damn my car looks dirty with the flash but it's clean I swear.
I can't tell you how the cable gets from the dash to the trunk, an installer did it. I do know he had to remove the rear seats and some obvious lining from the trunk. I'm sure you can figure out a good route.
The cable enters the trunk on the right side, is taped in place and routed along the right trunk hinge, and under the trunk lid lining.
The installer would not mount it inside the window because he said reception would be poor. I get excellent reception with the antenna mounted here, I was in the middle of a bad thunder storm last month and my XM was still coming in unaffected. A couple big steal overpasses in town and tall, concrete/metal buildings will still cause it to cut out monetarily. Overall I'm very satisfied.