Those brackets with the eight holes are riveted to the tracks and are not adjustable but the tracks are bolted (with clutch head screws)to the underside of the seat. If you loosen them you should be able to adjust the tracks enough to line up with the holes in the floor. Also, if the seat has been out of the truck for a while and has been getting knocked around those brackets that sit on the floor could be a little out of whack (bent), just bend it back.