I recently did this repair to my 320i 09 LCi rear light cluster, posted elsewhere however I thought this may be of some help to others although the great post by Brad bedell got me started and wouldn't have tried without his input on here, these are just a few extra helping points.
It worked a treat and you would never know the light had been apart.
http://www.bimmerforums.co.uk/forum/...ml#post1102625