Did you verify that it is the horn switch? I had a problem too where my horn would cut in and out. It turned out that the wiring at the disconnect for the horn was really deteriorated. Check that if you haven;t already.
Otherwise I would say the most straightforward way would just tap right off the relay that controls the horn.
Otherwise I think the horn wire may be green/black stripe. Try looking in the driver side kick panel. And maybe you can trace it from the coloum.
Just stay clear of those pesky yellow wires.
Linear Mode
