So whilst reinstalling the rear output shaft, with me not under the truck, the "hub clutch" (as GM calls it) fell out. It's the piece that looks like a synchronizer ring and that the rear wheel shift fork moves between the input gear and gear on the rear output shaft. I noticed once I picked it up, that one side is beveled and a hair thinner than the unbeveled side. (although that may be an optical illusion due to the small bevel) Anyone know which way the beveled edge should face? Towards input gear or towards output? Edit: Just dug a bit further into the '72 case I have partially apart, and took that ring out...same thickness on either end, (I'm measuring the thickness on either side of the groove cut for the shift fork) and it too has a slight bevel on the outer edge, but it would seem that the bevel is pointless. Hoping it doesn't matter... Thanks!