Finally got the rear end all buttoned up! Backlash wasn't quite where I wanted it to get a decent pattern but for an old truck and reused ring and pinion, it's good enough for me. Certainly better than it was!
Just got to replace the master cylinder and bleed brakes now. I'm pretty sure the last "new" master cylinder I got was a returned one. I remember the box had brake fluid all over it and the plastic packaging was ripped open. Leaking real bad out the rear ram. New one on the way.