[JamesM3M5]

You have to lift the manifold up a little - so there is some headache involved. I just unscrewed the 6 nuts and 1 bolt that hold the manifold down to the head and lifted it up a bit to gain access to one of the Torx head bolts that holds the filter housing to the head.

I would recommend washing down the engine and blowing out the area around the manifold-to-head interface with compressed air. It will remove any dirt and sand that has collected so you don't drop that stuff into the intake ports. Do not wash the engine without the cover in place, though. BMW states quite boldly in their manuals that the injectors are not waterproof and should never get wet.