Ford had numerous different finishes for their hardware ranging from painted finish to different types of plating. These finishes are found at the end of the hardware part numer and are annotated with the letter "S", followed by a number such as S7 being Cadmium Plate. "S" was a plain finish. Here is the chart that defines the specific finish.

I am always on the look out for original looking hardware such as these small screws and clips. Many of them are called for on the fire wall and the 10-24 cadmium screws are used for the transmission shift ring covers. They should be 5/8" not 4/4" and self tapping are not called for, but they help to seat.