Data files with very similar data extracted from the 1990 STF3 are available as filetype stf903x2.

Not only are the variables similar, but in some cases the data have been specially allocated to create 1990 data summarized by 2000 census geography (e.g. 2000 census tracts or block groups.)

The "parent" filetype for these datasets is sf32000.

This is where you can access the complete detailed tables as published by the Census Bureau. Those tables were the source of all the extracted variables seen in this (sf32000x) collection.