Does anybody know the NAPA part number for the spin on filter base that I need to convert my 8V71 MC-5 from canister type fuel filters to spin on? I'm getting ready to head out in a few weeks and while I do my annual filter change, I figure I might as well go to the spin on style. Looks like I can just bolt them right on where the canister ones are located now. I will try cross referencing the spin on numbers from the cartridge style and then see what the correct base is. Are primary and secondary the same base?FRed