Is the 1990 occupational code (occ1990) based on the BLS working paper?

I just want to confirm that the 1990 occupational codes for the CPS (occ1990) are constructed based on the guidelines in the working paper: “Proposed Category System for 1960-2000 Census Occupations” by Peter B. Meyer and Anastasiya M. Osborne. The note in the variable description and the embedded link seem to suggest that is the case (with only minor changes):

https://cps.ipums.org/cps-action/vari…

Yes, you are correct that the OCC1990 coding scheme is based off of the working paper by Meyer and Osborne. As you note, this is mentioned on the variable description tab for OCC1990.