real racing seats are measured in hip width. sit down on a flat bench with your legs hanging free. now have someone measure the width of your hips/'seat'(ie, your ass). most seats are speced in full inch incriments.
you also should check the back shell heigth as well, as quite a few seat manufacturers have varying seat heights.
"As the Z32 gets older and decreases in value it becomes affordable by lower income and often less desirable people whose tastes reflect their personality and social standing.- Marshall 17:37:05 10/10/03