There is a "Chrysler fuel nut" that is still available from any parts house
that will look up old car parts. That will replace the male fitting on the end
of the fuel line. If you've messed up the female fitting on the tank, that's
another problem. Because of the metal fuel line going directly to the tank
without a short rubber bit as on later cars, I've found that it's nearly
impossible not to strip the nut.
Cheers,
Roger