The originals aren't even comparable to each other. Hand hammered aluminum isn't capable of being exactly the same one after the other, or even side to side. It's been a significant issue over the years, to the point some have documented it to the fraction of an inch.
Hand formed body parts are exactly that, fabricated to a pattern - not stamped from the same set of dies like typical Maker cars.
The Mk4 was dimensioned from an existing car, and even then evened up to have the rear fenders at the same height, IIRC. Once finalized, those resulting parts are quite a bit closer to being identical to each other since they are laid up to one mold or pattern.
Cars made in a different facility, to a different set of patterns, can't and won't be identical. It's the both the beauty and the bane of hand formed parts - you celebrate their uniqueness and overlook the slight differences.
Follow the evolution of the 289 and you find over 6 different significant variations of body style, and I risk being questioned if I even have that right. Same for the 427, as production continued, changes were made. Even the Daytonas are divided into the first LA prototype, the "tall" Italian coupes, and the "corrected" ones. Given a chassis number, the Cobra fanatic can probably rattle off significant body features of that unique car.
It's the same with GT40s, although a much larger series - uniquely different parts pop up in the construction stream. It's all because they were hand fabricated - not stamped from a set of dies that literally wore out after years of use. And that can be seen, too.