Back when I was younger, from 1963 until 1980, there was a tent theatre in Milwaukee called the Melody Top. There's not a lot of information about them online either, however, I saw six shows there over the years:
Jean Pierre Aumont and Marisa Pavan in Carnival, 1969
Kaye Stevens as Mame, 1970,
Dorothy Lamour and Jack Bailey in Hello, Dolly!, 1971
Jane Powell in Meet Me in St. Louis, 1971
Gretchen Wyler and Linda Kaye Henning in Applause, 1972
Earl Wrightson and Lois Hunt in Gigi, 1974
Some of these may have played at Valley Forge as well. Later on, they brought in JoAnne Worley in Dolly and Anything Goes, and toward the end, they had either South Pacific or The Sound of Music every other year, usually starring Anna Maria Alberghetti.
Thanks for a pleasant walk down memory lane.
NYC Visitor and Broadway Fan