CD changer how to connect?

I don't know about the Sony, but I bought an Alpine (340? 360?) that is installed in my trunk. There's a Jaguar factory cable already in your trunk that's pre-wired to your radio. The Alpine is plug compatible with the Jag radio, so it was a simple matter of hanging the changer in the trunk and plugging in the existing cable. The cable is located in the right front corner of the trunk, hidden behind the trunk sidewall. When I say 'right front', I mean as you open the trunk and face into it, the cable is in the far right corner, above and behind the battery. I hung my changer on the right side of the trunk, fastened to the roof of the trunk. The Jag radio buttons control the changer just as described in the Jag owner's manual. Email me if I can be of any help. Paul