Rear view mirror question

My rear view mirror flops around like crazy! How do you tighten that up? 67 Plymouth Satellite.

Mine did too, I took it apart and added a o-ring on the ball part. Works ok!

Or you could hit the piece the ball rolls around in with a heavy hammer. That will flatten it out a tad and snug the ball so it doesn't flop around.

Thanks! Both ideas I had also but didnt know if there was something I was missing to tighten it up. Thanks