Looking for overdrive trani advice for /6, please help

I have another question: I know they had the feather Duster/Dart Lite in 76. What, exactly, was the automatic Torqueflite transmission that was used/available for this car? Was that transmission geared differently, did it have a lower third gear? Seems like I saw something about that somewhere in FABO. If so, I wonder if there are any of those transmissions out there to be found. Does anyone know the details that I am looking for?