1993 Mercedes 300E 2.8L crank position sensor - Where the heck is it? How do I change it?

internet said it is located on top of the bell housing drivers side.is it accessed from the top or the bottom? do I have to remove anything?

Let's start by you telling us why you believe you need to change it? 

Let me guess.  You had a CEL (Check Engine Light) and the code seemed to indicate a crank position sensor so you want to replace it.  There is no code that says "Replace the crank sensor"  You need to start by checking it not replacing it. 

  That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

If I remember correctly if you remove the exhaust pipes the sensor is easily accessible from underneath.

You call your Benz dealer and make an appointment…