727 yoke id question

I have a couple of yokes that were out of 727's, i wa looking at them lastnight and noticed a difference in the depth of where the splines begin, does anyone have a measurement or any insight into this? My transmission is out of a 74 new yorker. How far in does the yoke go into the tranny bottomed out, correct length of outside(seal surface) etc. Ive been throwing money at the dart like mad and need to mock a driveline up and cut it down to the correct length etc, this will be only for driving it to the paint booth and back. Thanks as always for sharing your knowledge.