You will need the engine computer for the Magnum (use '92-'95 Magnum computer-- for manual transmission if you're planning on using the 3-speed torqueflite. Either will work, the manual just cuts down on possible error messages when the auto tranny computer can't find the tranny it expects to see), as well as the engine wiring harness. You will also need to increase your fuel pressure with an electric fuel pump. Tie the engine computer in with a 12 volt power source and weld an O2 sensor bung into the exhaust. Really not that much to it for your swap. Go for it! As already stated, you will need a torque converter for a 318, that matches the tranny you'll be using.