I will describe how one type part changed color code identification over time. Below is a widely used B8AZ-9A523-L (marked BA and two scarlet red paint daubs by 1963) assembly in 4100-A carburetors of the late 1950s and in the 1960s. I have recreated original type and color paint daubs but for this post it is just an assembly to label areas of.
Area 1, the whole top side of the assembly. A similar part in the mid 1950s was usually dip painted with enough thin paint color code paint to cover all the exposed top side surfaces.
Area 2, the soft core plugs over the emulsion tubes. By the early in the 1960s paint daubs on the core plugs had replaced top side paint dipping. The C4OZ-9A523-B (marked M and a yellow daub in 1964) was marked with a yellow daub on the driver?s side core plug for 1964 and at least into the 1966 model year.
Area 3, most mid 1960s but not all models. the tubular struts between main tower casting and the two auxiliary venturi assemblies. By 1963 color code paint daubs were often only on the tubes. One tube could be daubed or both could depending on assembly. Both tubes could use the same color or different colors depending on the exact assembly. This type of marking scheme was used in production at least through the 1966 model year. The factory markings vary a lot in how large and neat the daubs are.
