I also have a '94 Dakota, 3.9L, and the same thing happened to me just two weeks ago. One ignition coil and one map sensor later (well, now I have two of each that work perfectly fine) I gave in and took it to the dealership. Turned out to be a corroded wire near the PDC. Four hours and $280 later I was back on the road…with a shiny new ignition coil and map sensor to display over my fireplace.
Have you tried checking continuity on the various 12V connecting wires, and ground wires? Since it was something that happened literally overnight, I wouldn’t have thought of diving into wholesale ignition system replacement - rather it might be a loose/corroded connection or a broken wire. If you had a British car - that’s probably where you’d have looked first. 
Maybe look to the 12V wire feeding the coil, or the coil ground, or the engine ground strap, or something like that - I haven’t traced an ignition system in a while to know what other wires are going to be important for you. Good luck.
That is what I suggested back in post #2
Ouch - good catch.
Yep - I am agreeing on the “broken wire someplace” notion.
I just have no clue which wires to even check. The needle in a haystack thing is a tad overwhelming.
Start with the fuse box. Ckeck each side of each fuse for power. Some fuses are only hot when the key is in the on position.
What you are concerned with is a fuse with power on one side, but not on the other.
Check for power at the coil primary (smalll terminals) with the key on.
Pull apart the connnectors apart for each of the items you replaced and look at the terminals. Do they look like they are tight and not corroded?
Frankly, if you get this far and don’t find it, it is probably time to take it to a shop.
My sincere thanks to all of you for your insights. I know it is nearly impossible to diagnose over the internet, but your contributions have given me some great leads.
If you have a repair manual for the vehicle and a volt/ohm meter, you may be able to perform a series of simple tests on the ignition coil, distributor pickup and/or module. The Chilton book for my old Ford van led me through a flow chart to determine that the distributor module was toast. Lacking manual and/or VOM, it’s likely shop time.
A common problem on these trucks is corrosion in the wiring harness under the battery/washer reservoir/power distribution center (fuse & relay box). If the “check engine” light doesn’t come on when the key is turned on (not to “start,” just to “on”) that’s almost certainly what’s going on. Look for greenish corrosion among the wiring (peel back covering as necessary). Typically a red/white wire is affected - it may even pull right out if you tug on it.
The pick-up coil (= signal generator = camshaft position sensor) inside the distributor works with a pulse ring (reluctor) attached to the distributor shaft. I have seen these pulse rings come apart, which results in no pick-up coil signal to the PCM, which results in no power to the coil. Another possibility is the ASD (Auto ShutDown) relay.
Check Engine light comes on - that one is not it.
So I would gather than a pulse ring problem is fixed by a new distributor?
Dude,
Check the connector anyway. It might be bad enough to cause a no start, but still allow the MIL to light.
While absence of the check engine virtually assures this is the problem, presence of the light does not eliminate the possibility.
Yes. It can also be replace separately (at least on some models), which requires partial disassembly of the distributor.
I would remove the distributor cap and pick-up coil and inspect the pulse ring. You should be able to determine if it has separated.
If it’s okay, probably the next easiest thing to do is test, bypass, or replace the ASD relay (you should be able to figure out how to test and/or bypass it if you have a wiring diagram).
To check for the wiring problem, you’ll have to inspect the harness in the area indicated. This may involve removal or loosening of some components for access, and removal of tape or split-loom (corrogated plastic tubing) for inspection. Usually the corrosion can be seen without totally unwrapping the harness. This is statistically the most common cause of the symptom described, but of course is more work than the above two possibilities.
OK - I can appreciate that. I thought the correlation was 1:1.
I will give all of this a once over when I get back to my house Friday. As always, I appreciate the help. You have certainly narrowed down the haystack which is hiding the needle.