So, I just took my recently acquired 2004 ES 330 on a bit of a road trip and the car runs fine, but I found out that the radio in it wont play a CD of MP3s in a folder and doesn't appear to have an input for an iPod, usb/aux or otherwise. This is the Mark Levinson system the car came with with the navigation. I guess in 2004 mp3/iPod compatability was not standard yet.

Anyways, my questions are:

- Is there a known way to hook an iPod up to the ML factory system or way to make the factory system read mp3 discs?

- If I replace the factory system, would that render the 6-disc changer unusable?

- I know if I replace the system, the factory Navigation will cease to work. I am okay with this, as if decide to go that route, I am expecting to replace the radio with something comparable to whats in there (for example, I'm looking at something like this: http://bit.ly/10qlHvB or this: http://bit.ly/13hTyGq ).

- If replacing the system, are there any general things I need to keep in mind?

Any hints, suggestions and comments are appreciated. If I can avoid having to take the factory system out, I would, but if I am I just want to make sure I do it in the smoothest way possible. Thanks in advance.