2003 f 250 wiring diagram

Does anyone know of a "free" wiring diagram for a 2003 Ford F-250 Super Duty pick-up? I am running an Air-Horn set-up and want to play with hooking it into the factory horn actuator (on the steering wheel). The intent is to have a toggle that allows me to cycle from the factory horn to the Air Horns. Also, where's the preferred place to tap into for a hot wire that is tided into the ignition (only on when the key is in)? Any help will be appreciated. Here's a pic of the set-up thus far... still have a few things to do on it.

IGNITION wire is a DARK BLUE/LIGHT GREEN at the ignition harness and the HORN wire is DARN BLUE (-) trigger wire at the steering wheel harness.Jeff

Velocity Custom Home Theater

Mobile Audio/Video Specialist

Morden, Manitoba CANADA

Velocity Motors wrote: IGNITION wire is a DARK BLUE/LIGHT GREEN at the ignition harness and the HORN wire is DARN BLUE (-) trigger wire at the steering wheel harness.

Awesome! Thanks!