You're right, it is a single screw. I just looked. (so I'm lazy and didn't go outside before....)
You probably can't get in there and reach the sockets, so you would just have to pop it (the lense) off. Don't worry aboot breaking the clips, as it was intended that the bulbs be replaced this way.
I have a full tank of Unleaded...
5 liters and 12 cylinders of fury....