Eight-squares exist in overwhelming numbers (a few million million by my guess, and 27 million million by Chris Long's formula), so there are many 'perfect' examples. A 1902 effort by Charles B Stewart had a two-word place name and word with an initial capital: decisive egomania computes impotent sauterne interned Viennese East Eden.
Word Ways: Vol. 38
, Article 12.
Available at: https://digitalcommons.butler.edu/wordways/vol38/iss2/12