the part of the wheel arch that i cud away does not need to be covered really, there is a whole section of the arch next to it under the same kind of presure as it and thats fine.
The majority of the bit i grinded wasnt covered by the liners, about 3cm was, the grinded section is about 5cm by 3cm. I have sprayed the section of the arch that i grinded with the stock VW silver.
Might use some kind of protective paint next, or work out someway of resealing it without that section.
I know someone who has run his polo gti without arch lining for almost 2 years without a single problem so
Phill.