Just with 2 years of delay!!
I managed to give it a try with that horn and was not able to get it work
In any case I had the front light broken as well so I order the following one from GM:
This one is coming with 3 wires. I can guess those are the + for the light, the + for the horn, and the common ground.
Anyone had already a chance to use it and could confirm the wiring?
Thanks!