Pretty sure the 300 ce 24V had the old Jetronic KE injection system so does not have a MAF If its KE it will have a big pancake type air filter on the nearside of the engine. If its the later system with a MAFF it will have an air filter box on the offside of the engine with a MAFF followed by a " cross engine" air inlet pipe across the top of the camshaft cover. This thread has a picture of a 300-24V [NO MAFF!] http://www.mbclub.co.uk/forums/mbclub-projects/29814-new-project-converting-my-300ce-300ce-24-a.html
Your MAF is 'mechanical'. If you remove the air filter housing you will see a sprung plunger that drops as air rushes into the inlet (or you push on it with your finger!). The amount of drop of the plunger is proportional to the Mass of the Air Flow.