1964 Dart 273 V8 factory service manual?

Get a 65 manual. The manuals are printed early in the production year, even before release. The dealers need them when the new models show up. I had never heard that the 273 was released after the new model year was but it's entirely possible. They were available in the 64 barracuda's and that model wasn't released until later in the year. All the websites say April 1 1964.