40th anniversary Edition Mustang GT....?
I'm sure you could find a site that explains the differences between the "standard" 2004 GT and the "40th Anniversary" special edition, but off the top of my head, there are a few obvious differences:
- 40th Anniversary Special Editions are available in Black, White, and Crimson... ONLY.
- SE's have gold "racing stripes" on the hood and decklid
- SE's have gold-tinted "Bullitt"-style wheels
- SE's have sideview mirrors that are painted the same color as the body
- SE's typically have no rear spoiler, but I believe it was an option to keep it.
That should be good enough to help you determine if it's a "standard" GT or a Special Edition.
Also, I've attached a link to a picture of a Crimson "Special Edition." The black or white one would be very similar.