Not a difficult job, needs some time to have it done carefully and safely.

There is a kind of glue/adhesive on the attachements (4) of the tank to the back of the rear seat. So you will have to pull a bit strongly when the nuts are removed.

You need a 45 mm wrench (if I remember correctly) to tighten the hose that goes from the tank to the pump/filter

One thing be extremely carefull with leaks when reinstalling to fuel tank.

Good luck

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Present cars:
My car: E-class 420CDI, 2008, W211, V8, 180 000km

Wife's one: C-class 220CDI Sport Coupé, Euro, 2002, W203. 345 000km

Son's one: GLK class, 220CDI, 2009, W204

Sold: E-class 260E, 1988, W124, Wonderfull car sold after 489 000 kilometres of reliable services (engine M103, clutch, brake system and 5 speed manual gear box all original).

Sold: E-class, 320CDI, W210, 2000, 225 000km