Cornell University Library of Gay men’s popular fiction collection, 1931-1992.
[Gay men’s popular fiction collection, 1931-1992. Collection Number:7456](https://rmc.library.cornell.edu/EAD/htmldocs/RMM07456.html#d1e137)
I found this link by accident while searching on Google. I never thought about a university maintaining a collection of historical gay fiction, unfortunately, it’s only an index of the titles in storage but you should be able to locate some of the titles via a Google search by author and title.
https://rmc.library.cornell.edu/EAD/htmldocs/RMM07456.html#d1e137
Source: reddit.com/r/eroticliterature/comments/10uq3cb/cornell_university_library_of_gay_mens_popular
proud to be a Cornell student