. . . . . . but it's rather easy to find . . . . . .
1) Upon arrival at the published coordinates, DO NOT TAMPER!! If you tamper you will violate State law.
2) Translate this State law as IL Code “ab-cde".
3) The cache coordinates are: N 41º 38.481 W 88º (52.218 + ab.cde).
This cache is part of a series – you've certainly determined its theme by now.
There is a puzzle cache which completes the series. Collect clues from the log sheets from the other caches.
Be prepared for variable road conditions.