That's exactly what I want to do. Pretty much don't need to use the factory horn and I am going to use the two hella supertones on the front behind the grill.
I have this wiring diagram from hella attached. I believe what I want to do is the bottom two pictures since I don't plan on switching between factory/supertones.
My question is I am almost positive we have the negative system so it would be the first picture on the bottom right?
Ie From the RELAY:
Pin 30: Fused line directly from the battery.
Pin 87: This is the 12v line from the relay to the + of the horns (I would ground each horn to the chasis right above via the mounting bolt, to make it super easy/less wiring mess)
Pin 85: This would be the + side of pulling out the connector to the factory horn? OR according to the picture another 12v source?
Pin 86: Would be the signal wire from the truck, or would this simply be ground? That's the only two things I'm confused about.
I want to do exactly that, remove/not use factory horn. But use the trigger that is normally used to use the factory horn to simply trigger the relay so when I push the airbag the horn goes off using the two hella horns.