I removed the glass from mine, which are not the folding mirrors, but may be attached the same. On mine, I moved the mirror until I could see behind it on the outside edge. There are little plastic clips (maybe 5?) at the back of the mirror holding it to the power motor. CAREFULLY pop one clip up with a long, thin screw driver (if you break it off, it can't be fixed and you'll need a new mirror) and keep pressure on the mirror to keep the clip from clicking back down. Reach in with the screw driver and click another clip. After that, the rest of them should be more accesible and the mirror easily click off the rest of the way. To put it back on, just line the mirror up on the power motor and gently press it down so the clips click on.
Hope this makes some sense.
David