can i put a 1974 318 in my 1994 1500
You have nit specified what motor is currently in your 1500. Any time you are installing a different size engine, there will be all kinds of problems. Starting with the motor mounts, exhaust system, Engine Control module, wiring harness, emissions, transmission, etc, etc, etc. This will be an expensive project. Additionally, if your state or county requires emissions inspections, it will likely not pass. So it may work but you could have troubles.