The part number 33326770786 has been superseded by 33321097009 according to the local BMW parts dept.
I will take a photo tonight and post it so you can see the difference. It does not have the flange and the outer shell is in two halves with a gap between each shell of approx. 3mm.
I would assume the new one will be much easier to remove, lets hope it does'nt remove itself whilst I'm driving!!!!