The internal/external resistor debate has been beaten like a dead horse. General Motors chose a non-resistor coil and a ballast resistor as original equipment for millions of vehicles for a couple of decades. The self-appointed experts on the Stovebolt site are smarter than all the engineers who designed those systems, I guess!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!