I left the key on my 12v, 52 3100, and burned up the battery. Dead, gone, fried. Got a new one and the truck wouldn't start. Checking for spark, I touched the coil accidentally. It was red hot and the truck hadn't even started. Replaced the coil, all is fine. Truck started right up. The new, and old coil for that matter, has "external resistor required" printed on it. I haven't found one installed anywhere but the guy at the auto parts store sold me one and said to run it and check the coil. If it starts to get hot, install this resistor. It's a BWD, part #RU19. There is also another # on the box. V12039. Should I do that or just install the resistor now? He sounded like he knew what he was talking about, but I am just double checking. Thanks in advance.