An eight-year run for the boxy sedan with undersized windows and an unmistakable oversized grille would have been enough for Stellantis designer Ralph Gilles to call the Chrysler 300 a success. Yet nearly 20 years after workers at Brampton Assembly Plant built the first 300 in early 2004, production of the car continues to hum along northwest of Toronto, even if it’s more a trickle than a flood.