Try to keep the rubbah fuel line as short as possible ,,,,more than 2-3’ and the hose can swell with each pulse from the pump and lower the delivery pressure @injectors ,,,,,,will act like an accumulator,,,,,there is reinforced fuel hose avail ( 2 layers of nylon / aramid cord molded in it combat that condition ! Double barb connector should work 🤔,,but some of the plastic molded tubing is kinda off sized on the ID value ,,,make sure the barb fits ( as in having to be “ pressed “ in place ,),,, it should not require a hose clamp on the plastic ,,,,,eye have a kit that hasa buncha brass connectors and the clamp -on. press tool for when the “ quick “ connectors @ the inline filters don’t come apart happily an you can buy the new connector wif a 6-12” piece of plastic tubing awl ready pressed onit . 🤗👍