Please someone tell me how to replace this before I go nuts on the headlight..

I unscrewed the one screw at the top of the unit and How the hell do I get to the parking light? I'm temped to take the whole side fender off just to get to it.

 

Not sure if it is the same for the impreza, but I just went through this same problem with the guys at autozone the other night. Ended up taking it home and taking off the grill and grill inserts on the side to remove the whole light assembly to replace a freaking bulb..