360 running on 4 cylinders

Compression, Ignition, Fuel

Have to go through all 3 of these systems and make sure each one is doing its job properly.

That includes fuel supply. Suspect that the '74 still has the original gas tank in it. You would be surprised how much sediment rust and gum is in the tank after 46 years.

Time for a new tank, sending unit and screen, fuel pump, and fuel filter for starters along with a fresh fill of Non-Ethanol gasoline.

That Ethanol gas really draws moisture and water in humid conditions, messing up your fuel system.

Not going to run right if you don't have clean fuel.