Right under the driver's door where the fuel lines run, where you have the 3 lines. 2 of them have the snap connectors and one is a plastic line connected to a metal line with a little rubber hose, what is that line for? The lil rubber connection hose was dry rotted n bout broke in 2 pieces

 

One should be feed, one is return, the one with the rubber hose is most likely vent. I noticed mine was gone when welding in my SFC's, just replaced it with a small piece of reinforced fuel hose, all well

 

The "third line" in the fuel line bundle is the line from the charcoal canister in the drivers side rear fender to the EVAP vacuum purge solenoid on the bracket on the passenger side of the intake manifold.