It would obviously be possible but unless something like that has been done before, you'd be on your own. It'd be easier to replace one of the existing ones.
I can replace the content of radio audio, and I can change the name of radio station will be displayed in game, and I also can change the icon of the radio station will be displayed in Audio Setting. With that abilities, I almost have my own radio staion. But the way that game must reference to radio station files by their old name such as EMOTION.adf, FEVER.adf, KCHAT.adf is the one thing I'm not really satisfied.
I'm learning about Programming, so I can understand a little about how the game run, a whole day searching but finding nothing to do what I want make me think it is very hard to change the radio station name will be referenced, it maybe have to access to the game program from the depth to change that.
Well, although I'm really a perfect at heart, there are something I unable to make it right my mind, I will accept it ^^
And I'm sorry for my bad English.