REAR VIEW MIRROR FELL OFF WINDECREEN

[Dimmy]

Hi...I have a BMW E36 and I accidentally knocked the rear view mirror of the windscreen which was glued on since I bought the car many years ago. I am going to buy the special windscreen glue to glue it back on. Having looked at the help videos they say best to detach the small round mount insert from the mirror first from the mirror so it won't be 2 heavy trying to glue the whole mirror back on until the glue sets. Then glue the small mount back on the windscreen then wait 24 hours before reattching the mirror to the mount. I have detached the small round  mount from the mirror but it's impossible to get back when on off the windscreen so it'll be impossible to reattach the mirror to the mount once it's on the windscreen..any ideas or is it not worth the hassle..just but a new universal mirror with a suction cup?..see photos.

[X5smw]

Do you not turn it and unlock? I’m sure mine did?

[Dimmy]

Yes eventually realised it twists back with force..Hopefully the same when I twist it back onto the glued centre piece when it's on the windscreen.