No horn on the 66 Barracuda

The B and C bodies with a rag joint used a jumper wire to go around the joint. Try hose clamping one temporarily to see if that's the issue.
Ahhh! That is a great idea. The shaft should ground thru the joint but a “wrap around” should work nice. Now to try to make it look like it belongs there.
I tried to ground the shaft with a ground clamp to battery and the horn worked perfectly. Thank you.
Syleng1