Removing the lower trim piece will facilitate pulling the entire lamp assembly out. With the hood open you can see that the inner edge of the lower trim is held on with a simple metal clip, remove it. The outter edge just kind of clips together, wiggle it a little bit and it should come apart and you will then be able to see how it snaps together and apart. Once you have the lower trim piece out of the way just do as Klaus says and shoot the four 10mm screws out of the back of it. Sometimes it is easier to get the upper/outter screw out of the back of it if you remove or slacken the hood catch so you can lean it out of the way. If you choose to do this understand that the hood catch also sets the closed hood height. Either scribe it so you can put it back where it was, be ready to adjust it when you are done, or fight with the bugger in place while you get that one screw out of the way. The only other thing I would check while I was in there is that the adjusters are all hooked up an working properly. From time to time I do get an assembly where one of the ball and socket style adjusters has popped loose and no longer works. Easiest way to tell if they are off is if one of the reflectors kind of flops around.

Good Luck,
Mark