Jerry -
I'm 6'1" and I installed spacers between the seat and the runners which were wedge shaped, going from one inch in the front to a wedged tip at the back, like a door stop. I made it out of some oak trim I got at Home Depot.
I really made a big difference and the upside is the seat is much more comfortable to sit in as well.
The only thing is I had to jimmy the front seat fixings a bit (I got a threaded extension nut and then used a bolt from the top rather than a nut).
Good Luck,
Alan