Dave, r those 18's on a Mk3??
No, there 17"s, they may look a bit 18'esq as the coilovers have dropped the car about 80-90mm

I dont need to know about the wide arches query as have just got a reply from the staff member at Redline
"Hello David
I have looked at the rear bumper below and its nice but i am doing something a bit different!!
as for the wide arch kit R&A are the importers and should be able to help you in some way and say were you saw it..
Good luck and look forward to seeing some pics
Tim"