Measure across your hips to determine the width of your seat.
1) Sit on a flat surface, preferably with your driving suit on and your legs 8 to 10 inches apart
2) Place a carpenter's square flat on the seating surface, and place it against your hip. Mark the square's location on the seating surface.
3) Move the square to the other side, and repeat step #2.
4) Measure between the marks, and you have your seating width.
5) Make sure the seat measurement fits between the roll bars in your car!

 B) Determine your Harness Type – “H” Style or “Y” / “V” Style

NOTE – Most restraint manufacturers have discontinued “Y” type harnesses as SFI will no longer approve them due to safety concerns.  Many now offer a “V” harness that bolts to the roll bar instead.  Depending on the distance mounted behind the seat, a single or double hole seat can work with a “V” type harness.