Wow, what a beast this thing is. My rear view mirror was sort of loose, but I couldn't figure out why. I couldn't see any way to take the mirror off, then
finally figured out that the mirror comes off the ball just by .... pulling it.
Once off, I saw the real problem was on the mirror shaft. There were a bit of play in the module the ball is held on by. I took the screw out to see the play caused from that area. Used a bit of foam in there to tighten that up with.
Putting it BACK ON was a real trip. I tried and tried, and was pushing pretty hard, I was afraid I'd break the whole down shaft. Finally it popped off, and I thought, oh, great. Now it's really screwed up. Turns out there's a springy looking thing in there, and also what looks to be electrodes. But I finally pushed it back into place, thank God no damage done. Now the mirror's tight!
jeff 1991 300d, 105k