It's narrow enough it will fit, not necessarily in the space saver wheel cut out but it will pack in the trunk. You can deflate the tire if you want to carry a can of air.
You could re-fiberglass the original trunk to get some more space or make an appropriate space for it, sure is easier working with fiberglass than magnesium! Kirk came up with a higher volume fiberglass trunk design back in 2009;
http://pantera.infopop.cc/eve/...=927100083#927100083
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