Yep. It was a prototype. Hand made one-off lets-see-what-we-can-do-in-the-shed build that was never meant to survive. I'd bet the builders would have done whatever they wanted, with wahtever was at hand, factory or "normal" Shelby processes be damned.
Hard to have latter day "experts" agree on how a one-off hand-made car "should" have been done! ;-)
But me, I'd call it more Shelby than not. I'll leave it to SAAC and others to decide... It's just a real good lookin' car to me.
Those late '68 reflectors on a supposedly August '67 car are a worry...