Okay, I have a couple of questions. I understand that the three main castings have different pinion diameters. I understand that axle shafts are axle shafts. My car has a 742 with 2.76 open ratio. I want to either buy or have a new third member built with 3.55 sure grip. Question #1 - If I have a 742, do I need to build or buy another 742 to replace it or can a buy a 489?
Question #2 - Will the U-joint/drive shaft work fine if I do find another third member that is not a 742?
Question #3 -...
8 3/4" third members
