[Formulajones]

Originally Posted by Greg Reid

Strange indeed...

If it helps at all, I'd probably chuck it up as an assembly plant thing. I wouldn't call one or the other incorrect. I've restored a ton of original cars from various brands, and if there is one thing they all have in common, it's very little

There are so many quirks and assembly changes, many assembly changes done right through a single model year in the middle of production runs.

Mustangs are terrible for this, with 3 different plants, there isn't much that is the same between the 3. One plant uses batch paint to shoot the floors, one uses red oxide, the other is black.
GM F-body plants are the same way. Van Nuys shot the floors black while Norwood used Red Oxide.
The number of production run changes on a 69 Z/28 alone fills a whole page. From gauges, hoods, decklids, spoilers, exhaust, it's just crazy. Takes a TON of research to do one of these cars correctly, any car really.