Did you replace the fuel tank? If the tank was bad enough to replace, the fuel line will be just as bad.
If the tank was good, chances are the line will be okay, too. But no guarantees on that... and if you have an old tank full of crud, a new line won't solve anything for long.
If you reuse the old line, disconnect it at the tank (you should be replacing all the old rubber hoses anyhow, fifty year old hose doesn't play nice with modern ethanol fuels) and put some air pressure on it. If it blows freely, you're halfway there. Then clamp the hose at the front of the car with a vicegrip and put air pressure on it again- it should pressurize, and if there are any leaks you'll be able to tell. Then I like to pump some Evaporust into it with a Miteyvac or equivalent, and let it sit overnight. Then blow it out again and pump some fuel through it until it comes out clean. Then hook it all back up with new (EFI rated) hose and clamps. Don't forget the grounding jumper at the tank connection, or your fuel gauge won't work.
Honestly, by the time you do all this, you probably could have just replaced the fuel line anyway...