If the centre diff had exploded then you wouldn't get 4WD, what it does is lock the front output to the diff casing, so you would still only have FWD.
Flapper EFi have a plain silver ECU under the driver's seat, a larger flapper air flow mater (volumetric) and you can clearly see the quadrant that the flap rotates in. The injectors run through a resistor pack under the airbox which is connected to the air flow meter by a short rigid plastic pipe, there's a 9th injector on the driver's side of the plenum for cold starts.
On a hot wire, unless youhave the uber-rare 3.5 with the early analogue EFi (larger, piano shaped balck ECU) then the 14CUX EFi has a square black ECU under the driver's seat, a smaller mass air flow meter marked either 3AM or 5AM depending on whether it was made by Lucas or Hitachi, the MAF is also clamped directly to the airbox. There is no 9th injector, the injectors run on 12volts in 2 banks, left and right. You'll also find the pressure regulator is part of the fuel rail on a hot wire.
Hot wire EFi came very shortly before the electronic speedo because it shares the signal (hot wire being far more advanced than flapper, an most were digital systems).
So if it was built in the 90's, it'shot wire
if it's a softdash it's hotwire
if it has the later electronic speedo, it's hotwire
if you have an engine warning light on the dahs it's probably hot wire.
