Help! Is this A833 stamp legitimate?

[PeniroN]

Do you think this stamp is legit?

The machined pad has obviously been ground. Has anyone ever seen this on confirmed original 833’s

The production stamp looks good and the date code seems to be correct for a 71 car.

I also put this on FBBO, was interested in FABO opinion.

 

[Inertia]

Might be an attempt to indicate a case change.

I have replaced many broken cases with whatever was closest to the top of the pile.
I never thought to alter the #s.

50 years later, I would never assume the guts were original .

 

[cudascott]

the factory numbers have been ground off and then re stamped so nope not legit.