Small block 904 vs /6 904, any difference to drive shaft length?

Hi all, swapping from a slant 6 in my 75 duster to a 360, will run a 904. Want to know if there's any difference to drive shaft length in the two set ups? I heard somewhere that the slant 6 904's had a shorter tail shaft, is that right? I don't have a spare small block 904 to measure to check.
my neighbor changed a 70 swinger from a /6 to a 318 and used the same driveshaft