I am 6'5" and I had the same problem, almost wrapping my knees around the ears driving.
So I bought a pair of seats out of an Audi TT. The good thing with those are that they have a lot of travel. The front mount on its rails I mounted about 1" back from the standard seats. Now I can move the seats fruther up front so my petite wife can drive, she could hardly press the clutch to the floor before. And I can move them so far back that the back hits the rear seat and I can have almost straigh legs when I drive.
What a difference. Then they are of leather so they are more comfortable. And they have heat in the seat too! good to have in cold climates.
Only drawback, I think, is that you get a little higher in the car. Not that I hit the roof but I would have liked it if I was a little more down in the seat.
Here you can see how it looks:
Four point harness has been added after the image was shot.
Jan