From what I have seen, which are not all Windsor-built cars, if that even matters, is that the full core support was painted with the rest of the car, as it was all "complete" at that time, which means it is body color, front, back, top, bottom. The "black" color is applied somewhat haphazzardly, rather than sprayed precisely, from what I saw at the dealership make ready and later of cars on lifts at the dealerships. The paintwork was certainly NOT to the same level of execution as the rest of the car, by observation, with some looking like they were painted with a "broad brush" or "quick spray angled from underneath".
End result is a generally dark background for the style and shine of the grille and related "bright" items to be in front of. Radiators and condensers were black, as were the related hoses, so what was behind the grille was all black (flatted satin rather than shiny). There might have been some exceptions for darker-colored cars, but I also suspect that if they were shiny (on a black car), it would have looked different, which I don't recall.
BUT, like other things related to an automotive assy line . . . although there were definite build instructions for each car at the corporate level, the EXECUTION of these instructions was up to the individual line supervisors to enforce or ensure they were followed. Which could vary from plant to plant AND shift to shift (at the same plant). Which can mean that things were "generally followed" rather than "specifically followed".
Which further means that if the black-out paint was applied with a brush, more differences around the edges can exist than not. In other words, take pictures of what YOUR car came with and then replicate THAT in any restoration activities.
Enjoy!
CBODY67
