Factory Primer Color

i think dipped first in a light green anti corrosion bath,then dipped as you say 22" deep in dark grey primer but oddly enough red oxide for California..then painted.Underbody would be dark grey primer with body colour overspray.
.. after paint all cars req'd undercoating in the wheel wells and trunk extensions and blackout on the front... some California cars rec'd black paint only in the wheel wells.
..But never say never in Moparland