Snow tyres? Are they legal out there in Switzerland then? Vicious bloody things that they are.
As an alternative, how about find a set of correct, original 1500 trims for those Dolly wheels that it's wearing in its pictures?
Or for another in-period look but same size as the Dunlops, so wide enough for the 175/70% tyres, how about Marina TC wheels?
Join the hilariously-named "Fastmarinaclub" forum and ask to buy some, just don't tell them what you want them for.
