Congrats! Beautiful car, and I too LOVE diesels!

The rear tonneau cover is standard in the BMW X-Series. Go back to your dealer and get it. We've had 4 X5s and 1 X3 (and my best friend just bought an X3 3 weeks ago...tonneau cover standard.

I have had several Range Rovers, 4 X5s, 3 MLs, 2 Lexus SUVs and 3 G-Classes....Tonneau covers ALL standard!