Are you asking if they used different width's of the mount bracket or different lengths of the starter generator?
Basically, there were two different brackets used on the Original Cub Cadet, one welded, one cast, and the cast one will fit the other 7 hp engines. The K-181 engine in a model 86 Cub Cadet was a bracket of it's own, but basically all the 10,12,14,16 hp Cub Cadet engines that used the starter generator, used the same part number mounting bracket.
Did your bracket, and the starter generator, come from an engine originally used in a Cub Cadet. If either came from an engine originally used in something other than a Cub Cadet, then yes, there could be some differences. There are differences in the Kohler K series engines, depending on the original application.