GPS Antenna Location

[biniecki]

I am looking at purchasing the GPS adapter for my radio here very soon and was going over the installation instructions and made note of where the antenna needs to be installed. It suggests that the best location would be on the roof of the car, the trunk deck, or on top of the dash inside the car sitting horizontal. I guess my question is, is there an easy way to run the antenna to the roof? Or and easy way to run it threw the dash without actually taking the entire dash apart to fish it threw an opening for a nice clean look? I was thinking of just putting it on the rear window but with it having to sit horizontal, that's out. The only other idea I had was to take the rear deck off again and cut a notch out for it in that. What do you think