I know this is an old thread, but perhaps my answer will help someone in the future. I had the same thing happen to me - mirror hanging by wires one day. I taped it at first, found this thread later, cried a little at a prospect of paying so much for repair (300 GBP is so much more relatively in Serbia than in the UK), and then fixed it :o) You need to take the door trim off, unplug the mirror connector, using a flat-headed screwdriver remove mirror cover (it is on the part of the mirror still attached to the door). If a claw in the cover breaks, you can glue it using a drop of acetone, since the cover is made of ABS. Remove two screws and one nut (nut removes from the inside - be careful not to drop it inside the door) and take the mirror out. Now, disassemble the mirror - take the actual mirror element out, remove wires. You will see a metal tube with two sets of notches and a fairly strong spring in the part of the mirror that was attached to the car (let us call it "bottom part"). Put spring and tube into the bottom part and use a clamp to compress the spring so that both sets of notches protrude (you might want to use U shaped stack of wood blocks to make room for the tube). Turn the tube so that second set of notches "catches". Remove the clamp. Put the upper part of the mirror in place (notches go through the slots). Twist the mirror like you are folding it. Tube will turn, releasing the second set of notches through the slots in the bottom part of the mirror. Put the wires back, connect them to the mirror itself, put everything back the way it was. Enjoy!