I have an 2007 A4 with the DVD Navigation/colour screen and the CD multiplayer in the glovebox - audio controls on the steering wheel. Question is it easy to go about using the CD autochanger connections to fit the Ipod adapter or are special skills required to fit? Does the autochanger need to be de-mounted for example? I realise that the CD autochanger can't be used after the Ipod adapter is fitted. Any help/opinion appreciated!