Help! What have I bought?

I just bought a 2004 Prius, and so far am thrilled with the car. I haven't identified which exact package it is, but it has the nav system, JBL stereo, and bluetooth phone support (which works fine with my Treo650 )

It also has had what looks to be a sat radio installation done to it. And done quite poorly it seems from the damage the person did to the dashboard vents when he/she did it. So I'm sure it was an amateur job.

I'm trying to figure out what exactly was put in, because it is odd to say the least.

There is what looks to be a Sirius-style sat antenna on the back of the car. Ok.... no problem. But here is where it gets wierd:

There are 3 cable run into the little cubby below the cd changer. There is what looks to be a tiny RG6-style cable, that I assume is the other end of the antenna. There is also a 12 volt line that runs back into the dash and comes out with a regular 12 volt adapter beside the 12 volt plug in the footwell.

Finally, there is a TWO connector teeny-weeny audio plug. Like a mono headset jack. I seems to be the same size as the audio connector for my Treo, but only mono.

This is puzzling to me. There is no way it can be transmitting stereo on that thing, so it must be some kind of control cable. But Controlling what? The radio certainly does not indicate any kind of sirius radio is hooked up.

Any ideas? I actually have little interest in Sirius, so I'm tempted to yank it all out, as long as I can figure out how to take the antenna off the back. I'm kind of scared what is behind the dash though.

As a follow up question, The person really did screw up the vent to the right of the steering wheel (the on/off control is actually punched into the dash and broken). Anyone know of a wrecker that has Prius dash parts? :-(

Pete