1964 dart carburetor

No factory 2bbls on a slant 6 until 1978. '64 would be a linkage type, not cable type carb. Those linkage type carbs were used up through the 1966 model year. They made both a Holley and Carter carbs those years. They pretty much interchange, but, there are some slight differences that might need to be addressed, such as the choke and pull-off, fuel line, air cleaner bail, and hose lengths. Mostly minor or not very significant. Jetting would be different between a 225 and 170, and also between auto and manual to a lesser degree.