I think talk of swapping the dash harness is just crazy. Mustang guys seems to do it when converting 4cyl cars. Crazy.
Your truck will have the same connectors, likely, as the Ex. So if needed, you'll just be either re-pinning a couple circuits, or cutting and soldering a few wires. Very simple work, and very easy to test.
(As an example, my truck has the same wiring as yours. I used the engine-side of the main conector from my 4.0 Ranger harness, removing most all of the 4.0 stuff, such as injectors, etc. My Mustang harness has three main plugs [two from driver's side, one from kick panel] that I simply removed and soldered the circuits to the wires exiting my Ranger engine harness plug. The whole thing is still removeable from the truck at the main connector, it's hooked up just like stock.)
Check autozone, you may find diagrams there (online, free)