so it is really easy to remove and replace all you really need to do to make it easy on your self is have a 17mm deep socket to remove the fuel inlet nipple its the rearward one when looking at the pump. then the pump should be easy to reach to break it loose then remove the rest of the way by hand... I fount that both the nipple and the pump only needed to be broke free then they both turned easy by hand so very quick.. the only hard part i would say is tightening it back down once replaced. other than that it was a 15min job to replace the O-ring and put it all back together..

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85 mercedes 300D-T 258k miles