So, next, I worked on the balls
I've seen a few different people rig up something to hold it in the lathe, but didn't see the need. I trimmed the excess tube just past the end of the knuckle ball with a grinder. Then you can use a 3-jaw chuck to grab the inside of the knuckle shank. Then ran a bull-nose live center into the machined inner diameter of the other side, worked fine. Just had to be carefull as I turned them, as I was working very close to the chuck. Carriage stop is your friend here.
I was assured my lathe was the latest model then I bought it
While I was working with the lathe, I made 6 other pieces to align things. 2 for the knuckles, 2 for the tubes and 2 for the differential. The knuckles, once the old tube is removed, have a 70mm outer dimension, which is 2.756". So they just need a little bit removed to be a light press fit into the axle tubes. The inner dimension of the knuckles is 40mm, so the alignment pieces are made to fit in there, from some scrap 1.75 x 0.250 dom. A 1.25" alignment bar is going through everything to hold it all straight. I used some pucks of aluminum to make spacers to fit in place of the carrier bearings. The bearings are 79.95mm OD.