It's a swine of a job - be prepared.
You need to remove at least one half of the bumper! And need Torx head and Philips screwdriver to remove screws.
Screws located at left and right of bonnet release (4 in total), 4 in wheel arch and one in fog light location.
Remove all these and the pull the bumper down. Meanwhile loosen the black screw at the top of the headlight and the two holding the underneath of the headlight to the body. Pull the headlight away gently but firmly as far as you can.
Flip the back cover clip away from the back cover; remove the cover and remove the electrical connection from the back of the bulb. Remove the bulb. Replace the bulb WITHOUT touching the glass - it's halogen and will burn out more quickly if you touch it. You don't want to do this too often do you?
Reassemble in reverse order and stow the spare screw that I had left over away for safekeeping and when you remember where needs replacing later.
Total time: two hours on first go without instructions.
Probably one hour the second time.
Make sure there is enough daylight left to complete. The wheel arch screws are particularly difficult in the half-light.
Note: You may need to move the wheels side to side a few times depending on the length of the too used to remove the screws - shorter is better!
Maurice Milligan, December 2008