Do you have the Bentley manual? Get one if you don't already.
Anyhow, removing the bumper is easy. Only takes about 10 minutes, if that. Just remove the front retaining nuts underneath the plastic trim, then remove the screws that connect it to the fender liners/underbody, etc. It should be pretty obvious where it is getting hung up.
There are 4 plastic rivets that are accessed by pulling off the black plastic grille piece from the bumper cover in addition to the plastic rivets you can see when you pop off the black trim pieces. If you don't get these off it's not going to budge.
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