The biggest part is the connector inside the console box between the driver & passenger seats. If you look down there, there's a wire that plugs right into the bottom of your iPod like the USB/Firewire cable you normally use.
FYI - You can just use the AUX plug and a headphone jack cable from your ipod's top to the aux plug.... The biggest difference of having the ipod connector is that it'll display the song name on your stereo instead of just on the iPod.... That and you can change songs using the stereo/wheel controls.
the answer to your question boys in on the scion.com page where you build your own scion.. juss looked at it a couple of days ago to see what i was missing buying my 2005 but i woudlnt have paid the extra money for it when the scion comes with an mp3 player already
The interior lighting as far as the dash is still amber. The stock 06 head unit display was more of a yellow, and I don’t think you can change the color (I only had it in for day). The iPod head unit has a color selector with about a dozen colors along with the ability for it to cycle between them (“Mixer”).