I was looking at the seats in my 95 extended cab they are buckets. It looks to me you could get the proper sized all thread and cut sections screw these sections into the bolt holes, assuming you have bolt holes and not studs, run a flat washer then a lock washer and nut down the all thread to tighten it down to the floor then two nuts and a flat washer the two nuts are tightened against each other to lock them in place at the height you are after. drop the seat onto these "studs" with a flat washer another lock washer and a nut tighten the seat down.
By the way Vintageman you have one of the exhaust systems I am interested in installed on the same
engine as I have. You don't suppose you could post recording of how it sounds.