Just because a wheel fits doesn't mean it won't have adverse effects on the car's handling due to incorrect offset.
http://www.whiteline.com.au/faqtyres...20who%20cares?
http://reviews.ebay.ie/FITMENT-GUIDE...00000001720675
http://www.tirerack.com/wheels/tech/...jsp?techid=101
The stock 18x8.5" rear wheels have a 52mm offset. The 18x7.5" front wheels have a 49mm offset.