I really hope this isn’t a stupid question, however here we go -1973 to thousand SC. I am looking to replace my ignition coil, now I don’t know whether I have a system that has ballast resistance in it or not. I have read some historical comments on here, about measuring the voltage to find out,however my question is do I put a meter across the positive and negative terminal on the coil with ignition on, or do I remove the wires that provide the power to the coil and take the reading from there with the ignition on? Quite simply earlier on I did it with the wires disconnected and I seem to be getting 12 volts, however when the wires were connected to the coil the voltage dropped to about seven volts. As I said I really hope it’s not a stupid question, thanks in advance for your help, Steve.