At 6'8" I think you will not be comfortable and having room for you legs to lift for room on the clutch pedal. I'm 6'2" I think have just enough room to deal with it in a 99-04 Mustang but it is by no means ideal.
The only way I honestly seeing you driving one in a stick comfortably would be after doing the very common seat track modification to get the seat to go back even farther. Even then I don't know to be honest...