33k mile 65 Riv

I have a 65 Riviera which has only 33,000 miles. I am cleaning up and painting the engine and engine bay. I have owned the car since 2007. The timing chain cover is the natural metal finish on my car. It looks like it was never replaced, but I can not be certain. When I look at pictures online, almost all have that piece painted Buick Green. I want to keep the car original. Does anyone know if the original engines out of the factory painted the timing chain cover or left it the original metal finish? How about the water pump? Thank you.