What year Bronco?
As you prob. know, colors change from yr to yr and sometimes withing model yr due to engr changes; BUTTTTTTTTTTT; I do have some on-line diagram links in my web site;
Under: ELECTRICAL EEC/PCM, power train sensors; wiring diagrams...
One of which is : AutoZone (under license from Delmar Publishers, combo of Chilton/Nichols/Delmar, & Haynes)
Ford Pick-Ups/Bronco 1976-1986
Ford Pick-ups and Broncos
Ford Ranger/Bronco II 1983-1990
Another sim. set can be found @
EBSCO Publishing (Automotive Repair Reference Center (ARRC)) - for 78–86 Bronco/Ford truck (76 to 86) (click on CHASSIS ELECTRICAL, WIRING DIAGRAMS in "Contents", left panel)
good luck mate!