It's not that easy . . . .
to replace that blub: must remove the complete assy by removing the burlwood panel.
To see how to do this, check my web page ('www' icon below) and select Menu #23. The pictures show how-to-remove it. Note some panels are one-piece but mine is a two section panel.
Once it's removed, you can remove the N22 control module. It's opens easily and you can replace the blub.
BTW, have to tried to 'tap' the LCD screen first??? You may be surprised!!!
Regards . . . . JimF
'94 S500 Cpe
Visit my Mercedes Web Page