Need help identifying thread size on the Fuel line going to the fuel rail. I have 2 sources telling me 2 different thread sizes. Both sound reasonable. I am just starting to replace all those lines underneath. Like M14 x 1.5 or M12 x 1.25 ... or 9/16th NPT...Not sure. Its is hard to trust the parts guy, I tell them there is no fuel filter there. They instist the thread is to the filter housing. I say it is different.