thanks Mike,I have that graphic,there seems to be some debate about whether the blackout was painted before body colour and then masked off,in which case there would NOT be any black overspray under the car....
Be careful. If you have a car that has rocker molding or side trim, say like a 69 Coronet, that would show the side of the rocker or in B body case lower part of the quarters, rockers, etc... this black was painted first. So in the case of the B body, you would only have body color on the under body where there is no black. On E body, you would have black on the under body from under the fender to under the front half of the quarter panel but you would find body color or may find body color under the quarter panel behind the rear tire and in the front part of the front fender. If you had a car that they only blacked out the bottom part of the rocker and pinch weld that was done after paint. So the under body would show or may show both body color and black. Hope this helps.