Do you have the factory bracket? Do you intend to only use the accessory horns, bypassing the need for the "Town & Country Horn Switch"? If so the wiring is straight forward. You'll need to run a heavy wire, probably 12 gauge, from the battery lug on the starter switch to the B terminal on the horn relay. Then run two wires, one to each horn, from the H terminal on the relay. Finally run a lighter gauge wire from the S terminal on the relay to your horn button. Unfortunately the pictures below weren't taken to specifically show the horns and relay wiring but you can get an idea of the setup. You can see the wire with an in-line fuse from the starter switch to the relay and how the horns mount. Hope it helps.
Save a life, adopt a senior shelter pet. The three main causes of blindness: Cataracts, Politics, Religion. Name your dog Naked so you can walk Naked in the park.