There is a metal fuel line that runs from the gas tank to the fuel pump. It runs along the top of the frame rail on the passenger side of the car. You have rubber hose that connects the gas tank to the fuel line. At the fuel pump, you have another rubber hose connection from the metal fuel line to the fuel pump. Running parrelle to the metal fuel line is a return line. Again at the gas tank, there is a rubber hose connection to the gas tank from the metal line. At the fuel pump, there is a rubber connection from the pump to the metal return line. On the driver side, there is a metal line that runs from the fuel tank to the charcoal vapor cannister at the front of the car. The vapor return line runs along the top of the frame. There is a rubber hose connection from the gas tank to the metal vapor return line. At the vapor cannister, there is another rubber hose connection from the cannister to the metal vapor return line. Note that if this is the original line, there should be a small metal restricting orifice in the line that should be installed in a new line if you replace it. The charcoal vapor cannister is located under the brake master cylinder, mounted on the small splash shield. With the age of your car, its possible that the leak could be a rust pit in the gas tank or one of the metal lines. Careful inspection of the fuel system should lead you to the source of your problem. One other point is the rubber hose that connects the metal fuel line to the fuel pump is a molded "S" shape hose originally. The molded hose is available from Corvette vendors. Some replace this hose with regular fuel line hose. If you do, you need to make sure that the hose isn't pinched off. If it is, you will have fuel starvation problems.
Good luck with your project.