Controversial & Contradictive
Inside of the boot behind the light cluster you will see a round cutout(round disk of carpet which needs prising open). There is a hex bolt(torx) in there. Undo this, and then swing the cluster away from the boot edge towards the front of the car. The cluster is hinged on the side of the car.
53 A4 2.5TDi Quattro Sport 180 Tiptronic. Heated Buffalino leather, DVD Sat Nav RNS-E, TV, Bluetooth, 6 cd, BOSE, Colour DIS, Cruise Control, Auto lights and mirrors, Interior light pack, Heated mirrors.