Be sure to pull the coil wire off so the plug wires do not arc against the engine or frame rails. A friend of mine pulled all the plugs and wires on a 440 MOPAR race car to clear the cylinders, he cranked it over and one of the wires arced by the head lighting off the fuel being blown out of the cylinders, they had a terrible time putting out the alcohol fire because they couldn't see where it burning!