360B: Girl Solves Mystery Using Library Newsreels

I hope I’m not blending info from several books, but here goes:

I read the Braille version of this book—probably about 200 pages in print—in the early 1970’s. I don’t remember the title, and am on the hunt for books I read as a young person—to re-visit them through older eyes. The protagonist may have been named Kathy Hughes or had a friend by that name. She solves a mystery using library newsreels. There may have been a male co-sleuth. Finally, the book may have featured an elderly  character in a wheelchair, Mrs. Smallett. Alas, that is all I can remember!

346P: Teen Mystery Centered Around a Library (Solved!)

It’s set in a small town where the main girl is a young teen/pre-teen and she lives with her grandparents and her uncle who is younger than her and is basically her little brother. They go to the library in town (the mystery of the book is centered around the library) and the library has a large mural of Andrew Carnegie burning in hell because the town hated him and refused one of his Libraries and built their own with a big “f you” to him in it.