CDC has their billet grill with the optional left side pony for the GT. http://www.classicdesignconcepts.com/shop/index.php?l=product_detail&p=105 It will fit the V6 with a few modifications to the bumper. Or you can get the GT bumper from http://www.newtakeoff.com/index.asp?PageAction=VIEWPROD&ProdID=7848 and it will fit as intended.
Just saw this overlay which is much cheaper. http://www.ssinserts.com/index.php?main_page=product_info&cPath=299&products_id=1189