Update #2:

Here are pics of the nearly complete fitment of the X5M bumper onto my 2013 X5 35i. My body shop dudes are doing the business! One more fill session, and the bumper will be ready for prep/paint and final fitment (..gaps present in the photos are due to the fact that the fender flares/bumper weren't fully mounted). Also, they made some additional holes at the bottom of the bumper where it mounts to the engine cover to bolt/screw the bumper sufficiently.





P.S. Damn, my FMI is smaller than a newborn baby.

P.P.S. muddycharles, as I assumed initially, no cutting of the X5M fender flares was necessary. The only modification needed was to the bumper itself (..to sharpen/square off the corner because it was rounded).