Nope. I love my cloth interior. I got my GT for under 27k brand new too, so you might be able to bargain a little more, especially now that the 13's are coming out.
That's what I was informed of too. They told me I needed GT500 tophats. It's not true. If you go aftermarket struts, then you need the aftermarket tophats.
Keep the fogs and go with this: http://www.americanmuscle.com/0509-black-pony-delete-grille.html
or
http://www.americanmuscle.com/0509-black-retro-grille.html#
http://www.americanmuscle.com/roush-billet-grille-0509.html
The 11-12's don't use the GT500 tophats. I bought them, and they aren't compatible. I did get an adjustable panhard bar though. Everything else was aligned within spec.