I don't know about any "pearls of wisdom" (as my oysters are ALWAYS empty), but I will give you some advice, and then tell you a little about how I did mine.
First, the advice.
Pull together all of the information that you possibly can before you start the conversion job. You do seem to be doing this already; good!
As you've already seen, there are several different ways of accomplishing different aspects of the 2.8L Duraspark conversion. Coils, carbs and tigers, oh no! Uh, sorry; wrong movie. Anyway, what I am telling you is, weigh through all of the information, and all of the details, make your own decisions, then get your complete plan, and parts, in place before you start the job.
You also have the '85 model, and I didn't see what transmission you have. Supposedly, there's a little more to wiring the '85; I know an '84 has the Duraspark (round) wiring plugs already in place, but I understand the '85 model doesn't. If you have the A4LD automatic, its overdrive function must be addressed.
OK, now my conversion. I've got an '84 Ranger, with the C3 auto (3 speed, no OD).
I bought the distributor, rotor, cap, Duraspark module, and can-type coil with a ballast resistor from a member here on TRS. As mentioned, I found the adaptor ring at Autozone (I researched it by crossing the application).
I also wanted to reuse my recently-rebuilt original Motorcraft 2150A carb. More research! A member here came up with a way to fabricate a manual metering block to replace the stock computer-driven solenoid. I made one and it works fine.
What about the emissions equipment? Guess what- MORE freakin' research. My truck still has the original catalytic converter, which I wanted to retain. The EGR was computer-controlled, so I removed it and fabricated a block-off plate. I kept the air pump, and just plumbed it straight to the cat. I just plugged the exhaust manifold tubes; it'd be a bear to plug the manifolds while still in the truck.
And finally, as part of my conversion I installed valve stem seals and adjusted the valves. It's easier done with the motor laid bare, carb out of the way, and well worth doing. The original seals were long gone, so my oil consumption was greatly reduced, the valves are much quieter, and I'm sure it helped the job-finished engine performance.
I couldn't be happier with the results on mine; and a lot of great people here helped me with advice and encouragement. This place rocks!
You've gotten some very good information from the others so far. Just remember, on the Duraspark conversion there are many options, several ways to do things; there's simply no set or one way to do it.
Sorry for the length of my post; but you sound like you're looking for all of the various information that you can get. Good luck, man!
Edit addition: Duraspark wiring harness plugs can be found in the junkyard on early '80s 4-cylinder Rangers.
