Which assembly plant underside paint procedure are you hoping to duplicate?.......They were not all done the exact same (I've been told).....Lynch Road cars (undersides) for the most part were painted the same at the Lynch Road......but not the same as a LA plant car's underside for example....just saying.

I was told this years ago about the LA plant and that black paint was used it some or a lot of areas of the underside but have never heard or read a detailed discussion or photo proof of this . My second owner '69 GTX LA assembly plant has a lot of underside black paint and it was original in places with black underside paint, never touched and spent 90% of its life in S, Cal and New Mexico. Still to this day it has a decal from a Norwalk California repair shop with no area code on the vent window of the car. Still wondering if there is any truth to LA assembly plant black painted B-body undersides done on the assembly line??