Ok im replacing the fuel pump on my car and both flexible lines from the tank to the hard lines were pretty bad. so i ordered 2 replacement lines from Mustang 86-93 Fuel Supply Line, Tank To Filter, Fuel Injection Hose W/ Factory Connections, 5/16'', 5.0, at LRS - Same Day Shipping! and they fit perfectly on the supply line. the problem is, the return line is smaller. What size is that line and where can i get the right part? thanks