Thank you for those reference shots, Carlos! They perfectly illustrate the article I posted earlier. Of the early F4U-1, it said the wheel wells and legs were the underside color, Light Grey (check!) and the hubs were silver (check!). However, as we transition to the F4U-1a, things change a bit with the move to the tri-color scheme. The wheel wells were the underside color, now Insignia White but the legs remained either Light Grey or silver. Nothing is said about the hubs.
Now I could stick to what this article outlines but I have photos of the actual aircraft and aircraft in the same unit serving at about the same time as the actual aircraft. I consider these photos to be more relevant than the SOP from the factory.
From the photo below, my eyes tell me that the landing gear legs appear to be lighter than grey and seem to match the undersides of the aircraft, which was known to be Insignia White. So I am going to paint the gear legs Insignia White. Unfortunately, this photo stops short of the wheels so for the hubs, I'm going to consider some other photos.
Below are some more photos of 740. The quality is not great but they show the wheels. The outside hubs appear dark in color with the center somewhat lighter in color. Are these silver or white hubs that just got dirty? Perhaps. But interestingly the inner hubs appear to be a lighter color corresponding to the landing gear legs. If the outer hubs were dirty, it would stand to reason that the inner hubs would be similarly affected, if not more so.
There are other photos of Corsairs from VMF-214. These are not the actual aircraft but since they are serving in the same unit at the same time as the subject aircraft, I consider these photos to be a more relevant reference than the SOP from the factory. These photos tell me that the coloration of the hubs could have varied from aircraft to aircraft. One has obviously light-colored hubs, either silver or white. The other two show a darker hub. Again, there is a possibility that these were lighter hubs that had gotten dirty but my eyes tell me otherwise. They are too uniform to be stains. They look to be painted in a darker color.
What that darker color could be, I do not know. It could possibly be one of the two blues for the upper camo since those colors would've been available. Here is a photo of another F4U-1a that served with VMF-214, #883.
I guess I'm not the only one who has guessed that the wheel hub color on some of the VMF-214 Corsairs may have been blue as this profile suggests.
I haven't decided what to do about the wheel hub color yet but I don't think it will remain white.