Canadian Valiant V8 Engine Color

I know that this might be off kilter but all three of my only US sold and titled Darts were built in Windsor - why would chrysler paint the Canada destined motors a different color???

By the way, at an all makes car show a few years ago in Port Angeles WA they assigned all the classes after talking to owners. Imagine my surprise when I got a trophy for... Best Import. Somebody knew what was up!