Question about iPod for 03' Bose & Navigation Stereo
 

A buddy of mine with a 03' Boxster is looking for the best way to connect his iPod to his stereo. He has the Bose and Navigation system option. He has a FM transmitter and says its sounds alright,but would like the highest quality connection possible. Anyone know of some sort of aux cable set up that may work? What are some routes he could take?