Ok first things first find a willing or not so willing child to do this for you because small hands and fingers will help if you can't find one, you'll have to do it your self !!

You access the bulbs via the engine bay no need to go through the wheel arch and it's fairly straight forward
on the nearside undo the screw to the power steering fluid bottle and move it out of the way. Then unclip the black plastic cover from the rear of the light unit (see last pic). Then put your hand into the rear and feel for the bulb I used a mirror to help.
Here is the bulb removed from the rear of the light unit



The Offside is a case of removing the top from the airfilter box putting it to one side


The bottom half can then be removed by undoing the screw near to the X on the word box! Also don't forget to remove the sensor also pictured I'm pretty sure this is the MAF which you need to be carefull with. If I'm wrong I'm sure someone will correct me



Then you have full access to the rear cover of the light unit this is identical to the nearside you can see the plastic clips which hold it on they're sort of covered in dust.