I would make sure they are 18" and if you can get them offset with 9" and 10" I would pick them up. I would make sure I put Saleen center caps on it though. It would be different and I would like to see it. Can someone photoshop it?
Or get you a set of Magnessiums off Ebay if you can catch a deal/break. I agree with everyone in that you should keep it "Saleen". Those are nice wheels however they belong on a GT.