six cylinder 4-speed Duster in 1974?

Was the 4-speed available with a 6 banger, from the factory, in a 1974 Duster? I've exhausted my google foo and need the forums knowledge. I did learn that they went to an overdrive in "75" using third gear for the overdrive and using 4th for 3rd by flipping the shift lever and effectively turning it into a 3 speed with overdrive. I found that very interesting.