That stuff isn't usually covered in the tech library. The nity grity usually has to be covered here in the forums.
I once had a 96' 4L I wanted to swap into my 93' 2.3. I was misinformed and misread information about the heads being different and causing problems when using earlier management. WRONG> A 4L is a 4L and the chamber will only affect operation when the 95-97 heads are placed on a 90-94 block. The later pistons are more domed to compensate for the smaller chamber in the head.
Now as for swap specifics.
Upper Intake, etc: You will need to get a 90-94 Aluminum upper and maybe lower intake. You'll also need the fuel rail and fuel injectors.
Cooling system: A 3L radiator will work. You'll just need the hoses.
Exhaust: If you have a early 93' Ranger with a 3L you may be in luck that the y-pipe will line up with the 4L's exhaust manifolds. Later 93' and 94' 3L manifolds are different and so is the y-pipe. So you'd have to find a 93-94' 4.0 y-pipe (they do sell it brand new at napa). A 3.0 uses the same catalytic converter as the 4L. If you are wondering......"why can't I just use the 96' y-pipe with the swap?" You can't (or won't bolt up)because the catalytic converter flanges are different.
As for the manifolds, I'm guessing the 96' has EGR. Just get a set of earlier manifolds from a 90-94 ranger or explorer.
Motor mounts: You'll just need the passenger side mount. The driver's side is the same between a 3L and 4L.
Air-Intake: You'll need the air intake tube, MAF, and airbox from a 93-94 ranger or Explorer.
Fuel system: You'll need the fuel line from the fuel filter to the engine. I think 96's are the same as earlier models from the hard lines to the engine but you'll still need the hard lines from a 93' or 94'.
You'll need a 4L trans.
Wiring/Electrical: What will make the swap a very easy and "non-suicidal thought" experience is the correct wiring harness. Get a 93-early 94' wiring harness and PCM. You'll need the harness from the overflow tank area all the way around to the PCM plug in and where it plugs into the white cannon plug on the firewall. You'll also need the on-engine wiring. And the correct harness for for whatever trans you'll be running.
If you are serious about this swap I have the motor mount, hard fuel lines, Air box, MAF, Upper and lower intakes, fuel injectors, rad hoses, and a few other little odds and ends. As for the wiring, get in touch with AllanD.