I opened the right rear door yesterday and heard the unmistakable sound of interference like when a fender gets too close to the hinge side of a door = instant damage, too late. Luckily, it turned out to be only the side trim which had apparently come loose at the front, and interfered on the matching trim on the front door.

I can see that I will need to remove this piece and have it's replacement painted before it goes on. Can someone guide me on removing this piece without damaging the paint on the door?

 

I believe these are put on with sticky tape. Carefully heating with a heat gun will allow you to slowly peel it off.

 

As mentioned above , use a heat gun carefully or a hair dryer, using fine fishing line or dental floss may also help with the removal. I have done this with badge removal etc.

 

Thanks. I thought all exterior trim used clips of some kind. I'll get this in to the shop and pull it off this weekend.

 

I have seen on the forums where owners have removed all of their trims for a smoother line on the car, similar to the 2006 models, obviously the side repeater lamp had to stay, personally I am very happy having them for a bit of extra protection.
On my last X350 I did a similar thing to you where it got caught on the front passenger door trim, it was not quite as bad as yours but I used some very heavy duty mastic adhesive and gently G-cramped it back in place, I left the cramp on ( with the door open ) overnight and was lucky it worked, I just did a small touch up to the cracked paint finish to tidy it up, the repair lasted another 3 years at least until I sold the car.