Testing if voltage is present, it's easier to just buy an ice pick volt tester. very cheap, no knobs. Just lights up, lots of uses. Nothing to drop on the floor.
Also, I keep saying...there is no ground from relay mount to chassis necessary on the horn relay. The ground wire from the horn button is ISOLATED to the relay coil. It is ground switched/triggered. Some folks may be thinking of a remote starter relay/solenoid. It's coil needs grounded by it's mount. All of it's terminals are hot and it is hot switched/triggered.
Scott, Wire your horn as we have described now that you know which thing is the relay. Follow the three wires on it first and see if where they go makes sense.
Do all this visual check and wiring with the negative battery cable DISCONNECTED from the battery post.
Sorry Scott, I called you Steve, I was dealing with a Steve somewhere and got mixed up. Very sorry.
