I used a small piece of dynamat to keep it connected to the glass mount and hot glue to stop it from vibrating at the joints. Still moves a little but doesn't fall off anymore ....

 

If you go to a speedyautoglass it's free or like $2 to have a rearview put back on. My rearview fell off twice from an RE XXX 12 on 1500W. 2 12's on 2000W will be really loud but I really doubt it'll do any real damage. If you snap a windsheild in half that's another story.

 

The mount stays on the glass, I couldn't keep the mirror on the mount. So I used a little dynamat on the base of the mirror then slid it into place on the mount, never fell off since.