Looking to identify and locate the horn wire, ideally under the dash, coming from the actual horn switch, before it gets involved with any other systems, polarity changes and such.

I am attempting to add an electronic airhorn to the vehicle and basically the method to attach is "find the wire coming from your horn ring and cut it, on the wire FROM the ring, connect a certain wire, and the wire going TO the horn, connect the other wire.

If there is somewhere else I can obtain this under dash would also suffice, but in google searches I found the wire is supposed to be on the brown plug and it's a tan wire. I hooked up a multimeter to this wire while vehicle was off and hit horn button. There was no continuity between this wire and ground, so I believe this is the wrong wire although I may have wrong wire?

Lastly, I believe the horn ring wire, once correctly identified should go to Ground upon pressing the horn button, if I am wrong I would appreciate some guidance on this. VERY frustrating

My ideal point of "splice" is tapping the circuit between the horn switch and the BCM, instead of between the BCM and relay. But at this point if I can identify either option, as to color and actual location of wire, I would be happy.