I can get the engine to fire up fine using starter fluid so to me, it's not a spark issue.
I can't hear a fuel pump when it's on, but never noticed it before. Also, I want to see if something else is cutting off the fuel pump before I replace the pump itself...
Coil pack could cause weak spark or no spark in certain cyl's, getting it to fire on already finely atomized starter fluid doesn't necessarily negate a spark issue. Did it keep running after starting? Also, I assume you pulled the intake tube, so you may have been racking on the coils unintentionally while spraying fluid into the TB causing it to work.
Yours is a 99 or newer correct? Which would have the Returnless fuel system, so there is VERY little obviously to go wrong between the pump and rails. A side-effect of this is that the FPR is actually part of the fuel pump assembly and IN the tank. If that goes bad replacing the pump alone instead of the full assembly could potentially not resolve the issue (just be aware of that).
There should still be a Schredier *SP* valve on the rails for you to see if you are getting pressure at the rails with a small screwdriver and a rag.
And like I mentioned earlier, late 90's ford injectors were not the best, but I'd still not rule-out Coils, as I've had 2 RBV trucks have bizarre-ass no-start conditions both caused by coils.
two other possibilities:
Crank sensor (which handles fuel timing, I actually had this fail on the Ranger swap, and was the only time I was ever left 'stranded' by any of my RBV trucks)
Sits low on the motor obviously, gets caked in shit, hot, etc, etc. 2 8mm bolts holds it on, about 10 O'clock on the Crank Pulley
Cam sensor (Also helps Fuel timing, but obviously key in Ignition timing, I have a spare or two of this and the Spindle assembly you are welcome to test with if needed).