Horn does not work

[camarojim]

Hello new to this site just bought my daughter her first vehicle she wanted an old Chevy Truck. I found a 1966 C 10 Fleet side Very Minor rust runs great looks good not perfect but very clean she had wanted a truck that she could learn about repairing and what makes them tick something that she could work on with me as a father daughter project. when we bought it i knew the horn did not work so i figured we could start there. the truck has been converted to a alternator with a built in voltage regulator. So the stock voltage regulator is disconnected the horn relay ties into the connector of the stock voltage regulator. Has someone out there converted their truck to a alternator and had this wiring setup that they got their horn to work i did not install the alternator so i am a little lost i got shop manuals on the way they are just not here yet. thanks in advance for any help anyone can give me.