The purpose of the pre-lube is to get all of the oil jounrnals filled with oil so that when the engine does turn over, oil is ready immediately to start lubing the critical areas and building a cushion of oil in between the bearing journals and the crank. You can also check the oil pressure before starting the engine. That being said , I don't know if you can adequately pre-lube with a screwdriver on a 6 cylinder. For instance, you cannot pre-lube a SBC with a screwdriver because there is an oil journal that you must close to get proper pressure, which a screwdriver won't do. Ask the local machine shop, you may have to buy a pre-lube tool for the 6.
