[Dave at Pelican Parts]

There are differences from side to side. The back side of the headrest has opposite angles; the edge slopes down toward the outside of the car. And the driver's seat has a divot next to where the handbrake handle sits.

I think--but am not sure--that on 70-72 driver's seats the divot is smaller than the later cars.

Obviously the 70-71 passenger's seat is fixed.

--DD