The 69 and 70 non cal cars had a tube with a vent line. The vent line just vented the filler tube to atmosphere and the line dumped under the car through the trunk seal. The aftermarket tank sending units for the period have either 5/16 or 3/8 outlets. The 3/8 also has a return tank line which is what you want. You can use that with the the filter listed above. You just need the return line back to the tank. Your 440 needs the 3/8 feed line.