My 50 has a horn similar to yours mounted to the boss on the intake. I do not know if it is original but I believe it is a period correct horn
The mount is diffrent than yours and it does not have that additional item on the bottom
To test the horn just ground one lug on the side of the horn body and power the other
...example... Im 12 volts and added a relay, not sure how the original one is wired.
