Thanks Alex,
What I'm after is to leave the CD changer cable in situ and hang "something else" on the end of it, either an old style USB dock or a converted-to-USB ipod dock. If this isn't possible I'll just put the blank bin in the armrest and add a 12 volt socket inside it for charging. It's really just for something to do that's different if I'm honest.
Regards,
John