Ballast resistors

1977 Dad drove us to the ski hill 2 hours from home in our new 1976 Fury Sport. Went to leave and it wouldn't start. Boosted it with a groomer even, but it would not start. Abandoned the car and fortunately caught the ski bus home just as it was leaving. Paid to have it towed all the way home a day or two later and all it was was the f'n ballast resistor. I've always carried a spare from that day to date. There is a spare in the glove box of every one of my cars, that way I'll never need them!