Smallest wheel that will fit an 04 XJR?

Just got an 04 XJR, and want to get a new set of wheels for it, mainly for winter use. Snow tires generally benefit from being narrower and taller, so I’d like to get the smallest wheels that will still fit the XJR. With its larger front rotors (larger than the XJ8 anyway), that may present an issue. Has anyone tried putting 18" or even 17" wheels on their 04-07? Thanks for any informed replies on this. Tigertank84

The 2002 XJR (including with Brembo brake option) used 18’s.

I did some digging, and found that the rotors for the 2002 Brembo brakes (355 mm) are 10 mm smaller than the Brembos on the 2004 (365 mm). Still possible the 18s will work, but won’t know until I find and try a set.