In addition to the things Mark said, you might also want this in the config.ini:

[serial]
car_rate=115200

This will allow the serial port output to run at full speed both in home mode and car mode (normally serial runs at a slower rate in car). Also remember that all of these config.ini statements are case sensitive - that has tripped me up before.

Here are some more details about editing the config.ini file.

I don't know what output you'll see for the radio; I know what the output is for the MP3 player. Here is some example code that parses the output for the MP3 player.