Im trying to get a 1973 Z28 up and going again and it seems to not have spark. I have been told the motor is a 1968 350. Cleaned points and distributor cap and plugs. Turns over doesn't hit once. Set the points to 15/1000s and try again, nothing. Take out a plug and ground it to block, then turn it over and there is no spark. Finally took off coil and tested it in an ignition simulator and it works. Haven't been back to the car yet. Any tips??