Well, Japanese cars are designed around Japanese people (average height of a Japanese man is only 172 cm, 5'7") so that doesn't help.

How good are you with metal working? The only thing I can think of would be to create a spacer bracket on the bottom of the seat to shift it a few inches to the rear. If headroom becomes a problem, you'd need an aftermarket racing seat (they usually sit an inch or two lower) along with a set of custom rail adapters to push it back.

Otherwise... sorry to say, but you may have to look into getting a different car that can fit your frame size.