I can verify what Longbox said. The jack is held in place by a spring that attaches to hooks on either side of a plate bolted to the floor of the cab in the back corner, driver's side. It could be the same set up as the Task Force trucks, but you could also be missing the mounting plate, as it just bolts to the floor. I removed mine to clean and paint it and clean and paint the floor before reinstalling the seat and a new floor mat. I've got the original jack but I would never use it. I keep a 2-ton bottle jack and some sections of 4x4 in case I need to jack it up to replace a tire. The small jack fits nicely in the same location as the original, and the 4x4 sections can be kept behind the seat, under the seat or just tossed in the bed of the truck. They don't take up that much room.
