factory undercoat question

Alaskan_TA said
The paint on the underside is from the dip process, check this link;

http://www.hamtramck-historical.com...hipDataBook/1972/72_Dodge_Engineering0010.jpg

So it would be the color of the final rustproofing process with over-spray from the painting. What color would that be? Mine isn't really black but its some darkish color.