You can access the fasteners that hold the side scoops on from the inside of the car by removing the interior quarter trim panels. First, remove the rear seat: http://www.bullittarchive.com/1002.htm
Be careful when working with the interior trim. Sometimes it takes a couple tries to get it back in just right and rattle free... Also, it cracks easily especially when cold.
If I remember correctly there are two allen screew along with double sided tape that hold the Saleen side scoops on. Your going to have to remove the back seat and the rear interior to access the opening to get to the allen screws.