I have a feeling that is my problem. It is an 80GB iPod video. It was purchased in April 07. If I place the interface into Playlist mode, the iPod does recognize it. It appears that the iPod interface isn't communicating to the head unit. I'm calling USASpec this afternoon.
thanks for the info,
Just to close out this thread for anyone interested: I got it in and it works like a dream. I just run all the audio through the stock head unit, and since I'm not really into blowing the doors off, I'm quite happy now.