HI I Have built a 55 chevy with a 454 I installed a hei ignition system in it. The car ran great. I moved the car out side to replace the head light switch.I disconnected the battery. Replaced the switch then connected the battery. The car would not start. Pulled a plug and found no spark.Repaced the modleand still have no spark.Check the power going to the hei coil and there was 12 volts. Any ideas?