systems and structures

I got pulled over last night on the way home.  I had a tail light out and the officer just gave me a warning...that was nice of him.  So I picked up the light bulbs at the store, replaced them, but it wasn't as simple as that.  Getting to the old lights were a pain because I didn't have the right tools.  Not sure if the new ones work because when the sun is shining bright into your lights it's hard to tell if they are in deed on.  So I'll have to wait until tonight.  I don't know why but sometimes the simplest of things (like changing a light bulb) can be more