I'm 6'3" and I find that I just fit in. With the seat all the way back, the base reclined as far as possible and the back reclined slightly I can get comfortable but I need to keep my hair short otherwise it catches on the headlining. Now that I've got my seat just right I'll kill anyone that moves it because I know I'll never find that sweet spot again!
As Leeroy mentions, I think the non-GT seats (ie cloth rather than leather and manual rather than automatic adjustment) sit slightly lower in the car, they might be worth a try - get along to a meet and sit in someone's non-GT spec car.