a833 with 904 yoke??

hello all, just registered to the forum and was wondering if someone had any information on this weird tranny i have. i have a 70 dart swinger i just converted from a 318/904 to a 340/4spd. i got everything together and tried to put a driveshaft out of another 4spd car i have and wouldnt fit. come to find out that the 4spd i just installed takes the 904 yoke instead of the typical 727 yoke. to be honest this is the first a833 ive ever seen with a 904 yoke. does anyone have any info on these kinds of trannies. like what they came in or what engines they were behind, or if somebody cobbled this thing together from parts of a 3 spd? any info would be helpful. thanks