Garmin 7200 - GPS/XM Radio/XM Traffic

I just ordered a new Garmin 7200 GPS, which comes with a 7" screen. It's a full GPS, and you can purchase an XM antenna to receive XM radio and XM NavTraffic. (XM Radio with built-in FM modulator).

It will fit nicely on the left front side of my dash, where I currently have a Cobra GPS with a 5" screen.

I have a 2005 basic Package 1 - no nav, no jbl, only a basic cd player.

What is the easiest and most economical way to direct connect the audio of the XM to my Prius radio (not concerned about the mdf)? The Garmin 7200 says it has a "3.5 mm stereo headphone/line-out plug". I have read all the posts for aux-box and vais, but still a little confused on what works with my 2005 package 1 basic unit.

Any help is appreciated. Thanks.

 

Just received my Garmin 7200 GPS. It's great! You can see my comments on GPSPassion.com.
However, XM through the modulator in the GPS unit is not that great in the LA area. Any comments on the easiset alternative (hardwired or AuxBox).
The Navtraffic is terrific (which is why I didn't want the factory GPS)!!