Tim,
You will have to decide for yourself on the oil filler tube color. All that I have are black. Even the one on the 5000 mile Fire Truck that had red over spray from when the truck was painted red. Skip Geear claims some were painted engine color.
Beware of "factory photos". Most were staged to be photogenic and not necessarily accurate. Photos of active assembly are probably accurate. Also lighting can give impression of a different color or shade in staged photos. Some photos are of prototypes that never made it to production.