I've been looking at old brochure pages of early '60's Johnsons-my year,'62-lists the 28 as simply a sea horse-a year or two later they are listed as "super" sea horse....what made the later ones "super"? an ad writer or actual change to design?
they were suppose to be lighter, and quieter. http://www.old-omc.de/index2.html
Which has what to do with the '62 28-horse in the question?