Originally Posted by sky

It's easy enough. Just look at the pics below and see the four clips on the inside of the caps...and look at the backside of the mirror which has the caps removed and see the corresponding clip slots.

1.) Tilt the mirror all the way up/down or sideways in order to get to each of the attaching clips. The clips are behind the glass and are integral to the caps.
2.) Locate the clips with a flashlight.
3.) Use a screwdriver to gently press the clips out of their retaining slots. (don't break the mirror glass!)