1931-1933 Ford Radiator Support Rod Cover Nuts (4). How about these highly polished stainless steel thread covers for your favorite Ford radiator support rods. They will hide those ugly threads! The short pair are 3/8" fine thread and are 1 1/2" long. They are for the firewall side. The long pair are 5/16" fine thread and 3 1/2" long. They are for the radiator side.