The clutch style is OK. I found if I use a rope with screwdriver as a turnaquet to pull the prop toward the front of the lower unit housing I can tighten and loosen the prop nut without going crazy.
found - '56 wizard super 5. getting ready to do research. but I am no engine guy and do not want to erase any value. This thing is about a 6-9/10?
757.503.0759 lower Chesapeake Bay
also found a '64 Evinrude sweet 16 for resto