So, I know there's a difference in the driveshaft yolk between a 904 & the 727 but, how about the output flange that bolts to the ball & trunnion? Different bolt patterns?

I think they are the same.I have B&T in the 65.I have a NOS parts at the other garage for mine.I think the /6 might be smaller as there are a few different ones made.Rocky

A flange behind a slant six 904 is different than a 904/318? So, that would likely be true behind a 3spd stick, 6 vs v-8? Thank you, by the way!

Yeah, there's two sizes, the smaller one went behind the sixes and some of the early 50's cars. Somewhere mid-late 50's with the more powerful engines they went to a larger one for the v8 engines. Can't remember the diameters offhand, but it's 1/2" difference I think, maybe 4 and 4.5?
Mike

I've had four different MoPars with a ball and trunnion setup. A 38 Plymouth, a 40 Chrysler, a 64 300 and a 65 Cuda. Only the 300 had the bigger B&T setup, it was a 413 with a stick. The rest have all had a smaller B&T.