In-tank fuel filter replacement
 

I am wanting to replace the in-tank fuel filter on my wife's X3. I lifted up the back seat and removed the metal hatch to expose the tank just fine. However, for the life of me I cannot get the lid loose. I have tried with just my hands and tapped it a little with a mallet on the "teeth" of the lid to no avail.

Is there a trick that someone has used in the past or a tool that can be bought to attach to the "teeth" of the lid? Also, do I need to unhook any of the wires/hoses to replace the filter?

THANKS!