need help with wiring!!!

hey im just about to put my kit on my truck but have no idea how to go about wiring it… i want to put the horns on my f250 and blow them with the stock horn button, but i want to switch between the stock horn and the train horn using one of my factory switches. thanks hope it makes some sense.

Are they 2 position…just on or off?
If so you’ll need to use a SPDT relay also called a 5-pin relay.
Power from your switch will only trigger the relay.

Cut the wire leading up to the horn.
The half going back towards the steering wheel goes to the center pin.
The half going into the stock horn goes to one side of the relay.
Then run a wire from the other pin to you solenoid valve.

I believe the factory upfitter switches may have power on them which will not work to toggle back and forth. But I’m not positive. If they are not powered then the number 4 switch will work. We are using it to toggle between stock fuel tank and aux tank.

That being said if they are powered just put a relay in. And when you flip the switch to train horn it will power the relay. Then when you press the horn button it will power the solenoid to the train horn. If need help I may be able to draw up a quick rough diagram.