I know this is an old post but I ran into a simalar issue. I have to run a part number 459 u joint its a conversion joint for 1350 to 1330 special. It is 1.125 caps on one side and 1.188 on the other. My truck is a 1994 f250 psd 5 speed 4x4. My axle is a 1987 f250 460 auto 4x4. It took me forever to find this due to the 1330 special joint. Hope this helps someone.