I'm personally a huge fan of the short story "Bloody Bunnies" by Bradley Denton. Most sources put the POD for that one at 1984. However, the range of changes seem to imply things went differently earlier than that. The story mentioned President Geraldine Ferraro, the crippling of the video game industry, emus becoming an invasive species across Texas, an alternate version of the film Groundhog Day, and a lot of other weirdness. Let's see if we can build a plausible ATL....