I changed mine not thjat long ago from the cream to the black one. Its just one piece, all you need to do is to take off all the fixings, and remove the top half of the door rubbers, and the piece around the edge of the sunroof, it should then just come out easily, then just reverse the process and it should go back in perfectly. If you are changing the little piece within on the sunroof then the sunroof will have to be removed.