From the Prince Restoration Guide ... section on 73-77:
Control arm cross shafts are painted semi-gloss
black on some cars and unpainted on others. Cars with
painted cross shafts typically have control arm bush-
ing retention washers and bolts that are also painted
semi-gloss black. Cars with unpainted cross shafts typ-
ically have retention washers that are gray phosphate
plated and bolts that are black phosphate plated.
Most of the ones I have seen are just plain rusty.
Maybe they had paint at one point - probably not.
I recall my 75 retention washers did not appear painted.