I have a chevy 63 c-10 truck and has a 350 motor in it..i have tryed count less times to start it and drained a brand new battrey in a day i have put it in the firing order auto zone told me 1-8-4-3-6-5-7-2 and still nothing i put a brand new coil,distributor cap and rotor on it and still not starting it turns over but back fires and nothing...any help would be great full