Fuel Starvation / Mechanical Fuel Pump

In my opinion... the factory mounted a metal filter vertically behind the lower rad hose and alternator at the same time the unleaded fuel came along. I took that as clue and did the same for current 67 273. Thickest carb spacer under my 2 brl was listed for 75 model 318.
I'll install the metal filter with port for return line in next build. It's not needed today. I do drive farther and pay more to get premium ethanol free fuel though.