You could always use a kenwood FM-mod (KCA-R71FM), it has full control, supports VIOT, its got audio outs if you don't want to use the FM interface, only a single line LCD though, but it works and you don't need to mess around to get it to work.
I recently put one into a friends car with a keg and as when the FM mod is switched on it disengages the aerial, its very clear, no hissing, no interference, I thought the quality would be useless, but was pleasantly surprised, didn't bother hooking up the audio outs directly it just didn't seem worth it, just stuck with the FM signal.
It cost me about £80.