It's not a shrouded mirror. The entire side mirror rides on a single ball-and-socket.

I'm single now, but don't plan to stay that way for the rest of my life (or even the rest of this car's life), so I have to preserve the capability of adjusting it for different drivers.

Believe me, I've looked all over for a way to tighten it. And removing it to replace it appears to require going from the inside of the door.

I'm not mechanically apt (and I pay the price for that), but the "replace it" suggestions are still appreciated.

I'm going to try the silicone caulk first, because I need to redo the tub anyway. Just a tiny bit, right around the edge of the socket, and try to work it down in by moving the mirror. I'll let you know how it goes.

Thanks