Yes, my previous post was lengthy. However, simply telling someone how to solve their problem is, for the most part, just giving "a man a fish." Walking through the process of finding the source of the problem is teaching them "how to fish."
Throwing parts at a problem is the "brute force" method ... often effective but usually inefficient.
So, your ICM. Your old one is clearly questionable, so get a new one. Expect to pay around $60USD. I've surveyed the market and all that I'd trust are in that price range. As with Leeann, I'd go with what Mancini offers. (Knowledge and experience is preferable, especially if they also have good customer service ... and that's Mancini.)
Yes, the ones offered by Mancini, Summit, and Moparts are all the same ... and four pin rather than five. Changing from five pin to four is easy ... many, many people have done it since Mopar changed from five pin to four. Mostly because the four pin ICMs are the only ones readily available. (The circuitry is simpler, which is another point in favor of changing.)
There's ample -- consistent -- information on the web describing how to make the change. The four pin OEM circuit used the two terminal ballast resistor but you can stay with the four terminal version. Various info on the web details both approaches.
I'd be inclined to stay with the four terminal resistor, because they cost less than the two terminal version. (Counter intuitive but factual.)
Note: The Mopar electronic ignition was identical across a wide span of makes, models, engines, and years. If you get one from a junkyard, it doesn't matter if it came out of a Dodge, Chrysler, Plymouth, De Soto, or Fargo. (I'm fairly sure it was also used in Imperials.) Likewise, everything from compact cars to medium duty trucks, as well as both small and big block V8 engines. (If it stops raining, I'll go out and look at what's on the V6 Dakota parts donor in my yard.)
Also interesting is many people have reported finding lots of unused ballast resistors in the glove boxes of various vehicles in junkyards/
I have found one aftermarket ICM I could reasonably trust. I have experience with what the distributor offers and they have a track record of adequate quality assurance. However, the list price is close to the available Mopar Performance one. (Mancini and Moparts' prices are actually a bit less.)
More to follow ...
