Another thing those late 70s Mopars were famous for was the ballast resistors going bad.. On the firewall will be a rectangular white ceramic looking thing with a plug on each end.. these acted like a fuse for the ignition system.. When they went bad it would not start.. Back then everyone carried a spare in the glovebox.. To test it unplug both ends and take a ohm meter and check the lower one from end to end and the upper one from end to end.. If either reads open then it is bad.. One side is the start circuit and the other side is the run circuit..
