Removing engine cover
 

I have a W211, E500. I plan to change the air filter by myself since the last "free service" by MB did not include the change of air filter even at 12K. I tried to remove the plastic engine cover without success and I was afraid of using too much force. Is there any screws or bolts holding it down? Looks like you can snap it out. Thanks in advance;)

Come on guys, I need your help. This should be an easy question for you experts.:)