There are two push button releases located between the seat cushion bottom and the carpeting. If you sat in the seat itself, it would be located roughly between your legs. I just carefully insert a flat screwdriver, and with a bit of luck, press the release in.
There are two brackets that hold the lower seat cushion in place, right along the front of the cushion. They have tabs right at the front of the bracket that you should be able to push in with a screwdriver. That will release the lower cushion, and you'll be able to pull it out. The upper portion just bolts right out. There are two bolts on the bottom that you can get to after you remove the lower cushion, and five bolts along the top.