I was looking at some 2004 Mustang GTs on a dealer's lot, and they all had a different badge on the side. It was an anniversary badge, and looked just like the V6 anniversary badge, so I don't like that about it.
Other than that, it looks the same on the outside, as far as I could tell. Same fake hood scoop, same fake side scoops, perhaps the rear badge still said "GT" (I don't remember for sure).