[Rainer]

Originally Posted by Hotrodpaul

Appears to be this one:

https://www.heartbeatcitycamaro.com/...GM%23-3829287/

The later 68-72 pulley I believe is 3.2" in diameter with no keyway slot.

I think someone machined the face to remove the numbers.

Thanks Paul. I thought it was this one since dimensionally its the same, but as you note there is no part number. The outer surfaces have some very light pit marks, so I don't think they were machined. I looked under magnification and did not see any evidence of previous numbers as well.