[T Scott]

Frankly, and in my opinion, buggard up threads from years of hammering and farmer fixing are beyond restoring. The metal is most likely work hardened, brittle, and cracked.
Reforming compromised metal such as this is not a good idea particularly with critical items such as steering shafts and axles. A better approach would be machine off the old threads, tig weld and build up the diameter to allow turning and re-threading. This is not a complicated procedure and I don't believe the tapered ends of axles or steering shafts were heat treated originally so this should not be an issue. This is what i have done, again , my opinion.