Cheers Richard. That's the kind of info I was looking for.

OK on the CD changer - need to check as it was changed out at some point - not sure if its worth buying a new version and flogging the old one on fleabay.

Re. the Aux-in cable, is this just a 'plug in to a vacant socket' type (ie an additional socket on the newer BM54) or does it need hard-wiring into the existing loom?

Once they have swapped out my Mk4 for a new one ( all I need now is to get them to change the BT ULF for the very latest ) then I will have a looksee at adding the Aux-in and perhaps swapping the CD changer over.

Cheers,

Mark.