I fitted the wind deflector yesterday and thought i would share a few things. firstly bmw part numbers mean the dealer tries to give you the 2 front black roll over covers. you dont need these, its the back silver ones you need that have the holes in. my dealer gave me a good discount and a bit extra because of the mistake, so dont be afraid to ask £220 all in including the roll covers.
fitting is easy, dont waste your money letting the dealer do it but the only hard part is taking off the old covers. there are no screws just stand behind the car with the roof down, grab one of the bottom legs of the silver cover and pull it backwards with your finger tips. it will slowly, and be patient, loosen as the plastic balls slide out of rubber holes. move round the cover prising each part off. try not to use tools but i found a bit that wouldnt budge and used a plastic windscreen ice scraper to push the silver bit away from the black and within 10 mins they both came off with no damage to either black or silver side. honestly it is easy, just take your time and dont get angry with it.
make sure you get the inner meshs in the right cover, they are marked R & L on the tags and they fix snuggly behind small square plastic clips. the new roll covers then push into place, make sure the holes are on the inside for where the deflector will go. the clip sections then screw into the holes (these are also marked R&L and the slide on bit for the deflector should be at the rear) the screws need an odd style driver but i found i had one with my drill.
with few practical skills I did it in 20 mins but just be gentle, take your time and make sure you get the left and rights correct. finally once on it is miles better than without even on a very quick test (well it is feb in england) and if you havent ordered your Z4 yet make sure you get it when you buy as it will be cheaper and save you having to do all this