Hey, StealthLee,
Obviously you don't know as much as you think! Yeah, the GT is just a name change for the GTP of 2005. The 2006 and 2007 GT, however, had the L32 modifications done and the engines limit out slightly lower than the 2005 L32, what does that mean? Oh, it means that instead of pulling mid 6's it pulss an 8 second 0 to 60MPH.
And finally, the one thing no one else has knowledge of is that the cars themselves have a 15 degree past 12 setting shift on third gear on the tranny. I told you I knew engines "N" Stuff. Nuff said.