57th Anniversary? Weird but I like the new information. Bought my first Mustang in 1970, 1967 2+2 toploader 4 bbl(not the hipo, to expensive and rare) and still own one today. I do like the Camaro/'Cuda/Challenger/AMX etc though, there were so many great cars back then. And so differentiated.
One of these many documents refer to the "T-5" project. In fact, when first exported to Germany, the Mustang was badged as the T-5. Later, as the "Mustang" was such a huge seller overall (and maybe the association of "Mustang" as the fighter plane faded in German memories) the proper name was used, at least until export stopped, and only restarted with the current iteration.
Just think... Such detail exists for every car we've seen in modern history; and many that we've never seen. I've had the opportunity to skim similar documents at Chrysler historical archives and they are FASCINATING, especially with the benefit of 20/20 hindsight. Maybe one thing to look forward to in our dystopian future will be the opening of more corporate archives now that such information has no competitive value. Thank you for presenting so much of it here.
The rebirth proposal of the 'Baby T-Bird' (2 seater +2) was good enough that it should have been given to the Mercury Division for a luxo-car. FORD Division was too parochial and gazing pitifully at their own navel to see the possibilities for that excellent proposal. A 4-speed High-Performance 289 Baby Bird with a modest back seat for gear or kids would have been a majestic seller for Mercury (which had NOTHING high-performance in their showrooms at this date).