Mercedes Vito w639 115 Cdi Seal Shaft Simmering 639.601/639.603/639.605 engine code

[Bodysoul98]

Hi,
I want to replace this simmering, I scrap entire front bumper, but how to extract the simmering, what Am I suppose to remove to acces it ? Poor mercedes, oil everywhere.
The simmering is located near cranckshaft like in the picture.