Transferred from old site but very useful So, to remove the painted mirror cap;This necessary if it's smashed or needs painting etc, and to gain access to remove the repeater lamp. Do not try to wack the outer cover from the inside edge. This method is more gentle and works.Using the electrics move the mirror max inwards, this allows you to get your fingers under the outside edge of the mirror and lifting near the centre, to pull the mirror of it's mount. That is the only dodgy bit of this, the fear being breaking the mirror. It's easier from now on.
See Picture 1
With the mirror removed you will see(just) precuts in the back cover behind. Open them up and you see the lugs of the painted cover. You need to insert a blunt flat bladed screwdriver in there and release the 2 lugs,the inner needs doing first.
The second pic shows the view from the outer side.
See Picture 2
The lugs, one at least is shown in pic 3, scratched but intact.
See Picture 3
This leaves the opportunity to change the cover, the light or the mirror itself.