1965 Dart GT "Charger 273"

Ive recently acquired a 1965 Dart GT with the "Charger" air cleaner and valve covers. How can I find out if this is a Charger kit original? I don't believe the car to be a real Charger Dart as it is black in color and by fender tag it is the correct color. The vin is L452545943

@65dartcharger