Engine compartment color

My dart has the original paint and there is zero black on the car besides the undercarriage. Under the hood is all body color and even inside the wheel wells.
Underside of car would have primer from being dipped at factory???? Right? Then they were either undercoated or just left. They got a little paint just below rocker from overspray. Correct me if wrong.

From every sign that I can see is that on this Duster its just the typical 40+ years of dirt, rust and grim over the original factory E coat. With no sign of the factory plum crazy color in these areas. Will follow up with photos later .. this eve..