Among other issues the wiring harness was a complete rat's nest of wires and electrical tape, so I harvested what appears to be a good replacement from a junkyard. The new harness is actually two separate components. The engine electrical with the majority of sensors and injectors fits well and lined up perfectly with all components.
In hindsight I should have spent a few more hours pulling the wiring harness from the chassis of the truck at the junkyard.
The 1987 F250 has square connectors and the harvested harness has round ones. The number of pins and color coding of wires is not exactly intuitive. I would guess that 85% of the wires match.
I would appreciate access to your service manual. I have Google Drive, Dropbox, iCloud accounts and such. Navigating this Ford-Enthusiasts' site seems to be more of a challenge.