Rebuilding my 8 3/4

Rebuilding a 489 case 3rd member isn't for the faint of heart. The only reason I say that is it uses a crush sleeve to set the pinion bearing preload with which requires a delicate touch to crush to the right amount to get the right bearing preload. You also need a yoke holding tool of some sort to hold it still while torqueing the nut to 240 ft. lbs. In addition to a press and bearing plate to install new bearings you'll need an inch lb torque wrench to set the pinion bearing preload with and a torque wrench that goes to 250 ft. lbs to torque the pinion nut with. You'll also need a spanner wrench to adjust the side bearing adjusters, a dial indicator to set the backlash. Race drivers to install the races with. One other issue is how to properly hold that 85 lb odd shaped chunk of iron still while your trying to torque the pinion nut to 240 ft. lbs. I built an attachment that fits my engine stand. Before that I clamped them down in my big vise and that sure ain't easy to get them to stay put do to their odd shape and believe me the last thing you want to happen is it fall out on the floor, or worse yet your foot. If that's the only way you have to do it make sure and have a buddy there to help so you don't get hurt or break something.

That's all I can think of right now but I'm probably forgetting something.

You might want to look on YouTube and see if you can find a video of someone doing it to give you an idea what your up against