In any handbook which shows the wiring diagram for the F350 for that year.
A complete diagram is available at MOTORLIT.COM.
Need to no what size engine.
you might try www.haynes.com
No, there is no wiring diagram for radio for the 1989 chevy capric on the internet.
color coded diagram for 1989 Harley FXR
http://www.commandocaralarms.com/wiring/1989/Nissan/Pulsar
no
could be the the headlight switch, dimmer switch, headlight relay, or a problem with the wiring
haynes repair manual or chilton repair manual, most often found at your local parts store
Try MOTORLIT.COM You can find the wiring diagram you need at autozone.com. that is where I go.
In the manual
Check the belt wiring diagram on the top of your radiator.