The following article provides detail information about radio installation and Wire Harness/Schematic process and procedures for 1999 Ford F150 Expedition. This 8 pages PDF file article outline procedures and instruction on how to remove your old radio from dashboard, wire the radio, mount the new radio, and finishing the installation of new radio, parts and tools needed for the installation process. Detail contents of this article includes Basic DC electronics for automotive applications, wire splicing: soldering vs crimping, why use radio installations kits, mounting your radio to an installation kit, why use an optional snap on wire harness, wiring your new radio using a wire harness, and testing wires when installing a new radio.
Find more about 1999 Ford F150 Expedition Radio Installation Wiring Diagram Schematics here. (source: installdr.com). Find also other interesting Ford Wiring Diagram (Fiesta, Mondeo, Mustang, Ranger, Sierra Cosworth, Taurus, etc).