[Rory428]

I`m no 429-460 expert, but my understanding is that the pre 72 429-460`s used the same pilot bushing/bearing as a FE engine . The engines after 72 used the much smaller pilot bushing/bearing, the same as the SB, 351W&C, 400 etc. Since the first 429`s came out in 68 Tbirds with automatics, maybe some of the early cranks were "oddball" in the area of the pilot, but I don`t know.
Regardless, if you do have an oddball crank, rather than get involved with expensive machine work, why not just get a used "normal" crankshaft with the correct factory piilot hole?