I don't even know how they can tariff building cars here. It's like a network of auto company plants and suppliers plants, trucks, storage yards on both sides of the border and it all moves around between foundries, stamping plants, steel mills, assembly plants. Just keeping track of what crossed what border how many times as the finished product was built, value added, etc would be crazy.
I believe the parts that go into those cars are imported and tariffed.