ClassicCar

I've never taken one out of that particular model, but GM typically used metal 'hooks' to secure the seats. Try pushing back on the bottom cushion and then immediately lifting up.

The seat backs are also usually 'hooked'. Sometimes you can see the hooks from the trunk area. You may have to remove some trim from the back of the trunk area to see them. If you can't see anything, try gripping the upper cushion on both sides and shaking it a bit. While you're doing that, push up on it. If that doesn't work, try pushing down. (I don't know how Olds made their clips.) On some cars, I've had to put both hands under the bottom of the seat back and do sort of a combination lift/wiggle. Just be patient and try as many combinations as you can come up with.

If you can get the upper cushion out, pull it away from the support gently. That is one of the most likely places to find build sheets on GM cars! If it's there, the paper will be fragile so handle if carefully.

Good luck!

Dave B.