Oooooooo, you are going to like this
just found this.
how to change the 3 arm flange on trans and rearend to a bolt on yoke, so no need to change to the 4 arm flanges and bolting on flanges, just unbolting the the flanges from output shaft on trans and the flange from the pinion on rearend and install the yokes, then measure out for driveshaft
just started searching for 27 spline yokes to modify and came across this thread, of what he did.


http://www.peachparts.com/shopforum/performance-paddock/255889-driveshaft-yokes.html