I know this is an old thread but it helped me get my fluids changed today.

I had a set of the above mentioned ez-red connectors which helped get the fill plug loose. Since I measured what I took out (600ml) I then jacked the drivers side of the truck up enough to extend the travel of the suspension and make it easier to slide around (no lift here). With that done I was able to use two wobble extensions from the wheel well to torque the fill plug back on.

As I am changing all of the fluids in my new to me 2012 X5D with 65k on the clock, I appreciate the time you had spent making these DIY threads Lambeau.