The T10 was always made by Borg Warner. It was the 4-sp of choice for GM, Ford & Chrysler in the USA, before the advent of their own Saginaws, Muncies, Top Loaders & New Process gearboxes.
The later financial structure is a bit hazy, but basically Borg Warner took over the Muncie factory (or GM took control of BW, whatever), but the end result was that the best features of the Muncie & BW T10 were combined to become the 'Super T10'.
The Super T10 was arguably the best US 4-sp of the era, with both Holden & Ford using it behind their respective engines in the later Group C time.
Dr Terry
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