Found out some interesting facts along with some mysteries and theories.
It just may be that even though the factory memo sheets that went out to NHRA depicting the exact thickness of the sheet metal may not have fallen into place after all like written.
Even though those memo sheets read off as .018 in thousands thickness, it seems that both NOS and used fenders from credible sources have read anywhere in the ballpark figure of .024-.027 in thousands thickness. Stock would be .038-.040
My friend Special K, thinks that a first batch or at least a first one of one stamping of the the sheet metal in .018 thousands may have resulted in very flimsy material at high speeds.
In contrast, the inner support braces may read anywhere from .035-.045 in thousands thickness. Stock would be .050.
Though some of these NOS pieces may have been dipped, they seem to have ended at the same thickness of my fenders which show no signs at all of dipping, Just thin slender fenders.
There was surely some funny stuff happening behind those factory doors way before the funny was put into those first Funny cars of yore.