I have a 1997 M3, bought used not long ago. The previous owner installed a sick aftermarket sound system, including an Eclipse CD8443 head unit. They left the factory cd changer in the trunk, which is still hooked up (has juice) but doesn't seem to be accessible from the head unit. Anybody have any ideas about how I can access it with this head unit, or what other head units might be compatible with the factory cd changer?
*(tried to post this over in the electronics category, but the site informed me that I wasn't allowed to post there.

used: )