A carb from another 40hp of the same year, would be best, as there were some Variations as the Years went along. From 1960 thru 62, the Carb had adjustable High and Low Speed mixture Adjustments, later ones had a Fixed High Speed Jet(with an exception in 71, but that engine was based on a different Block). Up till 64 the Electric Starting Engines had a Hot Water Automatic Choke, from 64 till 67, a Hot Air Automatic Choke, when it was replaced with a Thermo-Electric Choke, in 1968. A couple of years later, it just became an on/off Electric, or Manual Choke, depending on Starting System. Also through the Years there may have been some slight changes made to parts of the Linkage that interact with the Armature Plate. In 1971, Evinrude/Johnson switched a Powerhead from and different Division, and I don't know what changes occurred with that one.
While a Carb from years other than the same year as yours, will bolt on, it might take some swapping of the Peripherals on it, to get it Compatibility
