The Tragically True Adventures of Kit Donovan by Patricia Bailey
My rating: 4 of 5 stars
Despite my dislike for the "gutsy in anachronistic ways girl lead" genre, this doesn't irk me as much. Possibly it's because in the Wild West gender roles were often somewhat nontraditional, with girls given more freedom than their Eastern counterparts. Having said that, there is a large dose of improbability that adult readers will have to swallow; younger readers won't have read as much and will be swept along by the plot to notice.
ARC provided by publisher.