Before I further hijack the original poster's thread:
1) That same older thread I linked to above has a procedure from pre-68 dave where Loctite and an oven help take up spindle slack.
2) There are a couple very nice Tech Tips on the site which discuss kinpin replacement and spindle bushings. Worth reading.
------------------
Since it's on my to-do list anyway, and we keep linking to a thread from 2013, I will volunteer to carefully document and share my misadventures in 1/2 ton AD kingpins. Reaming, honing, sourcing parts, etc. I know I have significant play particular on passenger side....but haven't yet torn things apart to see if it's in the axle or spindle or both.
Hopefully get to that before spring time. But if someone beats me to it....all the better.
Can your eyeballs tell you where the bulk of wear is at (axle or spindle)....if you watch it while a helper moves the pushes on the wheel to create the movement? I know this is no substitute for tear down and inspection. Just curious if it might help get a guy thinking down the right path.