Have you checked the Auto Zone's web site? They have a free maintenance section there. Ya gotta sign up, but it's free. Also Ford's site has an owners section that's free too. They have Owner's Manuals for download. Don't know how far back they go.
If anyone had the image for a 85 F350 that would really help. I have the Haynes manual and the wiring diagrams at the back are very helpful the diagram for the fuse box leaves something to be desired. Thanks.