Resuscitating this old thread. I have an '18 King Ranch 250 arriving in mid-April and it too has the backup alarm. Read through the whole thread but it looks like Beezil's pictures (page 5 of this thread) which I assume included a wiring diagram of sorts are no longer available on Photobucket (d#mn Photobucket!). Does anyone have or might be able to draw up a diagram of how to wire in the relay to the upfitter switch? I understand I'll have to run a wire from the alarm's hot side to the cab or under the hood somewhere but from there am a little lost. Any help is appreciated!