Flip fuel cap on Duster need to be vented?

Well then... I do believe I have some revisions to make in my fuel system....

I have the 1/4” line on the passenger inner fender under the hood and believed it was a fuel return line and plumbed it as such with a fuel filter that has the third orificed nipple on it. I knew the evap thing was missing but hmmm... now what... I haven’t been running it long like that, only plumbed it that way in November and drove the car 20 miles randomly before decommissioning it for safety rework...

My fuel sender has an extra nipple on it that has a hose and and bolt plugging it off currently... could use that for return and remake a vent hose out back somewhere... or add a vent hose in filler neck, or ... someone smarter than me can just tell me how many dollars to make it right and I put it right???