you can look out for A20RYM as his car has...20 inchers on
The only work I ever had done was when I had my 8.5 x 18 Breyton Magic Replica's fitted and there was a very slight rub from the 225/40 18 Avon tyres on the rear arches so I had the lip on the rear arch rolled. After these I had two sets of 19" wheels and 235/35 19 tyres fitted.
After a NEW wheel was released by TSW I calculated the figures and found that the 20" wheel and tyre combination was actually very slightly smaller in overall circumference.
Have I had arch mods done YES, was ANY further arch modification done to house the new wheel and tyre on to the vehicle??? NOPE:rofl
Click on my user name and check out my photo albums to see how low it is too:thumbsup