Air filter C-class 180cdi

[sceh]

Dumb question but before I start fiddling about to remove the filter box I thought I'd check since it seems things can be screwed up easily with the MAF.
Here is a photo of the filter box of my 180cdi. I has an odd aluminium box of unknown function on top. Can anyone tell me how to change the filter and which screws to remove?

thanks

 

[sceh]

the thing on top is the solenoid and ECU but does it need removal to change the filter?

 

[sceh]

This is getting worse. I am told that when you replace the air filter you should use a diagnostic tool to reset the AFM adaptions for which of course you need to have a diagnostic tool.
Is this true?