Just a few comments, how do you turn the engine off if you don't use keys? If its hooked to the coil negative, you fry the contacts cause the coils puts out one final spike around 300 volts when turned off. Thats why old points systems used a condensor to prevent points pitting. The relay or switch should be on the B+ side of the coil. Also, a standard ignition coil draws 6 amps. The relay needs to be rated higher than 2amps. If you hit a bump or lose power to the relay does the car die if it's hooked in series with the coil? The LED needs to be currrent limited to about 10mA. Do you have a resistor in series with the led or is the 1200 ohms you need to limit the current to 10 milliamps built in? I am not knocking you, just don't want you or anyone else to have problems down the road or on the road.