2006 Ford Fusion Tail light bulb replacement

Open your trunk. Where the plastic meets the cloth liner of the trunk by the lights, there is a single plastic button-bolt (I can't think of the actual name). Anyway, if you pull on the plastic cover that the bolt is holding in place, it will pop out. Then just peel back the cloth liner and you have full access to the light assembly. It's just a simple turn and you have it out.

I have an 06 Fusion as well, and had to do that quite a few times due to my being lazy and not getting a new bulb. I recommend getting a bulb that has a plastic fitting on it so that it will lock into the assembly.