The factory installed rado/cd is terrible and it doesn't play mp3. What brand or type of radio/cd player can I buy that wll fit to replace the factory installed one?

Yes - the OEM sound system is horrible. I tried replacing just the speakers at first, the but sound was still terrible.

I got a double DIN adapter for my truck, bought a Pioneer navigation system and installed it all myself. Now things are much, much better. I have bluetooth integration for my phone, a good iPod interface, a decent in-dash navigation system -- and the sound quality is really good.

I think the bluetooth interface and the sound quality are better than the Bose system in my wife's Infiniti, although it was not cheap.

I got just the pioneer radio with cd player and the XM sat rcvr and get very good sound at a reasonable price. I got mine at Best Buy and at the time I got mine they installed them for free, including the sat antenna, which I had them go above the roof liner and come out thru the third brake light. Reception great from that position! I did have to purchase a new wiring harness ($19.95) and it has an ipod connection.