playing live tv from your phone to your car headunit

hi everyone!

I wanted to know if anyone has hooked up their android phone to their car headunit to play videos. If so, can you please help. I wanted to know what equipment you need to play the video from your phone to the car headunit (if you have a screen obviously).

This is what I have planned. I plan on buying a kenwood headunit. I am also buying a slingbox so that I can watch live tv on my HTC Evo. I would like to be able to connect my Evo to the kenwood headunit so that I can watch my slingbox on it. I have seen it done on youtube with iphones but they have to be jailbroken and they just play it using the ipod adapter cable. The kenwood headunit i am getting has a usb cable but as far as i know, if i connect the evo to it, it would function as a mp3 player. If anyone can please help me on what else I would need (equipment/cables, etc) to be able view my htc slingbox to my car stereo headunit, I would greatly appreciate it.

Thanks y'all