I expect Dave Van Riper will take care of this specific request via email, but to address the general question for the forum:
1980 block data tables are in fact available through NHGIS. They are, however, somewhat hidden because the 1980 Census summary files use a non-standard block level definition.
For most years, block data are provided at this standard level:
> Block (by State–County–Census Tract)
In 1980 Summary Tape File 1, block data are instead provided at two different “compound levels”:
> Block [1980 STF 1, MCD states] (by State–Standard Metropolitan Statistical Area–County–County Subdivision–Place–Census Tract/Block Numbering Area)
> Block [1980 STF 1, non-MCD states] (by State–Standard Metropolitan Statistical Area–County–Place–Census Tract/Block Numbering Area)
The first of these levels is used in “MCD states”–states that have sub-county governmental units, which the Census refers to as “minor civil divisions.” Illinois is an MCD state, so its 1980 block data are provided at this level.
To find these levels in the NHGIS Data Finder:
Click on the GEOGRAPHIC LEVELS filter box
Click on SMALL AREA STATISTICAL UNITS on the left-hand side
Click on SHOW COMPOUND GEOGRAPHIC LEVELS in the upper right
Scroll down to find a listing of all compound block levels
(Some more explanation: In NHGIS parlance, a “compound level” is one that consists of intersections between non-nesting standard levels. E.g., “County (by State–Place)” is a compound level because counties don’t nest in places… Some places straddle county lines, and some counties straddle place lines. In 1980, unlike in later years, official block definitions did not nest within all larger census units. If a block straddled place or MCD boundaries, the 1980 summary tape file reports data for the block’s split parts on separate lines, and there is no single record describing characteristics for the _whole_ block.)