Rob, Mk1 was made 96 - 98 - they are all R reg, none were S.. the Mk2 came in then..
Dunno if it can be done.. I know my 195/50/15s on a -35mm drop at the back needed some arch work.. but then, some people have 17s on the RT.. I guess it depends on offset of the alloy - Im guessing tho you WILL need some arch mods.. heh.