Actually that is not true at all. The only vehicles manufactured by Ford during this time frame that used rear brackets tie downs were the Mustangs and the Cougars. Other vehicles like Thunderbirds, Lincolns, Broncos, Fairlanes, Falcons, Comets, vans and trucks used existing holes inside of the frame rails for the rear tie down hooks. Because Mustangs and Cougars didnt have anything like this and for clearance purposes they added the brackets on the back. Its actually unique to the cars that we are talking about here.