thanks for all you comments, had planned to get the rims diamond cut but never got around to it!
The undersides of the arch have all been sealed with some "black stuff"!
As I said the only prob is the gap between the plastic arch liner and the plastic arch trim (now bonded on!)
Bodyshop is called Maryport Car Centre and is in Maryport, Cumbria (Lake District), about 30 miles south of Carlisle. Doubt any of you will be anywhere near!
Will 185/45s not throw the speed a mile out? 185s are got narrower wheels arnt they??