This is the stop for the back of the seat rail. It bolts to the back of the seat rail using the same bolt that holds the seat to the car.
Kevin,you get new seats? Or pull out the existing ones?
I never messed with them either. I installed the LETSLA shift kit and was adjusting the cables, so I moved the seat up to pull the console. This piece was just sitting on top of the rail, looking rather lost and forlorn.:shrug: I never messed with the seats.