slippydrew wrote:
I was told if I enabled disk use AND manually manage songs, it would allow me to do this,
I don't think so. Disk use allows you to use the iPod as a storage device - as far as I know you cannot play music while it's in Disk mode, nor can you take audio from the USB port on the iPod. (I'm sure someone will correct me if I'm wrong!). Manually managing songs is the method for adding or removing content from the iPod, not a means of controlling it from a head unit.
Whether you can connect your iPod to your car and how it will work depends upon the car, model and year of manufacture. I used a Dension adaptor that plugs from the Dock connector on the iPod to the back of the stereo in my Mazda 3. I can choose any album, genre or playlist but usually I set the ipod to "shuffle all songs" mode and then plug it into the adaptor. Once connected, I can control track skip and track back from the steering column but I cannot see track information on the car's display. The iPod turns off and back on with the car ignition.
However, my sister-in-law has a Mazda MX-5, but her (Bose) stereo will only play from the first five playlists and that's it! Quite who thought that was a good idea, I cannot imagine! I believe this issue has been corrected on newer models.
So you see, two models from the same company give different results. Oh, and by the way, when I had the adaptor fitted, my supplier tried to sell me an FM transmitter type adaptor and I recall having a very heated discussion with them about this as they had already fitted the wired adaptor I wanted to a friend's Mazda 3.
My advice is that you see a car audio specialist who can then advise you (properly, I hope) on what options are available to you and your car. Look up Dension though, but treat with caution their claim about using USB. I've noticed that you and Kenichi have exchanged a few more comments while I'm writing this, so I now know you have a Sony head unit. It may not be able to display the iPod screens, but I'm sure Sony make iPod adaptors for their head units..
I still think you need to consult a car audio specialist, who knows what they are talking about. I think even your local Halfords may be able to help. It can't help to try them.
Phil.