I'm using a full size Platinum 22' rim in the spare tire carrier. Fits perfectly!
Luckily I purchase 4 PLAT rims with usable tires as one of the factory tires just broke a belt at 17k miles and I just grabbed one off the shelf and installed it so i didn't have to lower the spare.
I plan on keeping 2 of those rims and tires. I have 2 I'm willing to put up for adoption. If you are in South Fl if anyone is interested.