You're right there. Luckily the inner wings and boot floor are rock solid. Won't know what the sills are like until the kit comes off. I'm tempted to remove the kit myself to save the bodyshop doing it and so i can clean it up while the car is away. What puts me off is that i may inadvertently damage it. I'm expecting to lose a few clips but i would really be upset if i damaged the arches or the sills. The plastic must be really brittle by now.
Any tips from anyone who has done this would be very welcome.

Many thanks.