Get in back, facing the rear of the car with your knees straddling the hump in the center of the floor. Push in, (towards the rear of the car), on the bottom of the seat base. It should release and then you can swing the seat up. They can be stubborn, but this should work.
BTW- If you have long legs you may want to move the front seats all the way forward first.
Bob Von Kaenel
70 SS 402ci+.030 TH400 3.73 posi Cranberry Red
We've not been called upon to hold the fort, but rather, to storm the heights!