My understanding, and please correct me if i am wrong. is that the iPod adapters do not show text on the display. The units i have seen work from playlist's. most seem to only be able to handle 5 playlist's. you can then track up and down in that playlist. or select another playlist.
I think the way they work is, the playlist apppear to be CD's to the HU, so you would select a playlist like a CD in a CD changer.
There have been many discussions about if/how this could work. and i dont know of anyone currently working on such a device. In fact, as far as i can find. all research on the 3 radios has stopped. I have been doing some research into the audio electronics sides of things but thats it so far.
ZC