I would be prepared to replace the kingpins and bushings. I went through this last fall on my 58. They were nice and tight, but I couldn't get new lube in. I removed the zerks, cleaned them up, and squeezed new grease in.
About 10 cycles of the steering later (on blocks, not even driving) the kingpins had loosened enough that there was about 3/16" of play at the rim of the wheels.
When I pulled them out, the old hardened grease had been the only thing keeping them tight.
