Peter - what you describe is very familiar. I did the same to the OSR wheel arch about a year ago. Hell, this is going to be expensive, I thought. Showed the deformation to the dealer, whereupon he said "What we do is to get hold of these bits, you push and I'll pull" - and Bob's your uncle. All straightened out and no cracked paint. Parking sensor? Excellent idea, especially with two brick pillars either side of my drive entrance.
