If it's anything like mine, which I would bet they are exactly alike, then 20 minutes is being generous. The bottom section of the rear seats comes out independently of the top part, and actually does not have any bolts holding it in. All together I can get the entire rear seat, top and bottom out in about 10 minutes. Also, there is no carpet under the bottom of the rear seat. It stops just after where you can see it. Just take that rear seat out, move the sound proofing crap, and drill away.
To take the bottom part of the rear seat out just feel along the bottom edge of the seats where they meet the carpet. In the middle of each "section" you will find a little white plastic things with a slot in it. Insert a flathead screw driver in there and pull up on that section. If you were sitting on either side the plastic thing would be bewteen your legs, just to give a reference. There is one on each side. Once you get the sides lifted up, just feed your seatbelts thourgh the holes and lift the entire bottom part out. All together. top and bottom, there are seven small bolts holding our rear seats in, scary isnt it. Even more scary is that all of those bolts are in the top half of the seat.