I've been trying to verify the authenticity of this "vintage" jazz bass neck's authenticity. I haven't seen it personally but here are some quick facts by the seller.
- there seems to be no visible marks at the heel to indicate it's year
- serial number is not present in the neck plate, it's not marked with an F either
- 4-bolt neck
- Fender stamped tuners were replaced with gotoh type tuners in the 80's
- The neck is maple with black bounded fretboard and block inlays.
- trussrod adjustment is in the neck heel instead of bullet type.
I compared it with a jazz bass i saw off ebay with similar neck featuers
- the string guide doesn't seem to be the fender standard type
- The jazz bass decal doesn't seem to end at the right place, i noticed that usually the last S of the word bass, would fall just beside the tuning peg hole(though it looks proportional)
- the tuning peg hole seems smaller than usual
hope that some forumers can shed some light