<VV> Carb Production Error

[Grant]

I just came across a '64 HV carburetor in which GM failed to drill the slot for the ported vacuum tube (to the distributor). It also had a partially drilled hole
for an enrichment needle and non-symmetrical base, so probably a later piece. It had seen some extensive use, so the owner probably had to deal with some issues.
I have not seen such a thing in any of the 15K or so carbs I have taken apart. Wondering if anyone else has ever come across such an anomaly?
Thanks,
Grant