Take the two screws out of the front of the airfilter housing which sits on top of the engine (the flat black bit with "Duratec" written on it). Then all you have to do is lever it off the rear two posts on which it is located and held there by rather grippy rubber washers. this can be difficult and you may give up because you think you might break something. You can unclip the large air inlet pipe (on right as you look at the car) and the small breather pipe in the middle. You should then have enough manouverability to turn it over and take out the ten screws holding the two halves of the housing together.
Shaun Leighton, May 2008