You will need the screw-driver with a crosswise edge.

1. Remove decorative facing of an arm of fastening of a mirror to a door …	2. … turn out four screws of fastening of an arm to a door …

3. … also remove the left external rear-view mirror from the car.

4. Similarly remove the right external rear-view mirror.

5. Establish external rear-view mirrors as it should be, the return to removal.