Headlight bulb: H7 12v 55w
Tools needed/used: Jack, axil stand, small adjustable spanner, star head driver (for wheel arch cover bolts) and torch.
Time: Half hour to 45 minutes
Had this job over the weekend on the girlfriends KA (drivers side). It was far to fiddly for me trying to change it from under the bonnet despite my smallish man hands. I ended up jacking the car up on the drivers side, removed the wheel, put an axil stand in place (never work off a jack!), and removed the wheel arch lining (about half a dozen star head bolts and a regular bolt). This gave easy access to the back cover that houses the front lamps. As you look straigt on, the top lamp is the headlight, bottom light is main beam, and the light to the side...well that's the side light.
Anyways, looking at the back cover, was a case of flipping downwards the metal clip that holds the cover in place, then removing the cover fully.
Just pull out the black, plastic connector to the bulb.
Flip downwards the clip that holds the bulb in place (before doing so, note exactly how the clip sits when holding the bulb in position, will help when you have to put the clip back again)
Insert new bulb (note there's a tab on top of the bulbs metal base that sits in a slot in the bulb housing) making sure it's sitting flush in place. Avoid touching glass of bulb with fingers if you can.
Flip upwards the clip that holds the bulb in place
Push black plastic connector into back of new bulb (might want to test the light works before boxing up).
Replace black plastic cover by slotting downwards and pushing foward so as the seal is flush all the way around the cover.
Flip upwards the metal clip that holds the plastic cover in place.
Now screw wheel arch lining back on and put wheel back on the car as you would if you had a flat tyre.
This may seem like I made a meal of it, but is better than the £50 odd being quoted otherwise for a garage to do. Halfords weren't interested either btw.
Thanks for the above advice - just changed headlamp driver side in 20min approaching from top side
A few tips after my experience:
Don't try by this route if you have big hands
1st remove water cover (rear cover - black plastic) by lifting metal clip - cover drops back but must be removed entirely to allow space to disconnect electrics and to manoeuvre your hand (note has 2 retaining protrusions at lower end which must be carefully rehoused at the end to maintain the seal of the unit) - comes out with some careful manoeuvering
Disconnect wires - connector pulls off the 2 terminals at base of bulb with ease - as above do this before disengaging metal clip that retains lamp
As above be sure to take note of how the clip that retains the lamp disengages for later reassembly
Lamp is now easily removed - hold terminals pincer-like between finger and thumb to carefully remove noting the orientation of the tab at its base
Insert new lamp without touching the glass and taking care not to disturb the reflector cone
Reset lamp retaining clip - it is a bit fiddly
Take care when replacing the back cover to ensure that two retaining guides at the bottom return to their slots before closing up - if not final metal retaining clip may still engage as if cover properly seated leaving the electrics exposed to loads of water
I removed the bonnet stand and set it up on the passenger side to give myself a bit more room
Tools required: nimble hands, torch (bright head-torch ideal although I used a conventional and rather dim hand torch)