The rearview mirror on my 87 300SDL vibrates and it appears the day/night adjusting mechanism has worn out. There is a lot of play in the mirror itself and I believe it needs replaced.

I have located an MB replacement mirror, but have been unable to figure out how to remove the old mirror. What is the best way to remove it and reinstall the new one? Or is there an adjustment to tighten the mirror up...

Well, the mirrors are designed to just break away. A good swift tug should release it. Now, getting the new one on looks like more of a challenge. I bought a replacement mirror because mine was discolored on the back side of the glass. I have yet to replace it as I am worried that I won't be able to get the new one on.

Many Threads Ago...
 

This problem has been covered before. You can do a search in the archives for mirror, rear view mirror, etc.

The jist is this. There are screws that secure the breakaway mounting to the car that can loosen up. Also, the mirror itself can loosen on ball socket at the end of the stalk after time, and the flipper that changes it for night driving can, but seldon does wear out.

Give it a good hard, but careful, pull and remove it. Check the screws to see if the mounting is good and tight, and see if the problem is in the mirror assembly itself. A real inexpensive fix can sometimes be an application of RTV silicone adhesive to the ball socket, or flipper to help dampen the vibration. But try the mounting screws first.

And, come on Q, you're a big strong man. Replace that mirror!:D