Fuel pump location
It is inside the gas tank.
Try This: http://forums.mercedesclub.org.uk/showthread.php?t=100565
Also, look here: http://www.pelicanparts.com/techarticles/Mercedes-W203/74-FUEL-Fuel_Pump_Replacement/74-FUEL-Fuel_Pump_Replacement.htm Good pictures and procedure. Double check its for your variant
Are you sure your problem is actually the fuel pump? What is the indications that led you to this conclusion? Sometimes a simple changing of the fuel filters, cleaning of the injectors, or fuel system is all that is needed. Water in the tank? Gas cap plugged? If I was working on you car, these are the things I'd check first. To safely replace a fuel filter, it is expensive as it is labor intensive so you don't blow things up, like helpers, friends, cars, garages, or houses. Even forbid the beer cooler would bet damaged also.
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