Stop in for a cup of coffee

Ddaddy said

Another little secret is that almost all of the 5 pin stock replacements are actually a 4 pin internally and the 5th pin is a dummy. That makes the second part of the dual ballast useless and can confuse the hell out of someone trying to solve an ignition problem. Because they are 4 pin internally, they also carry the ignition advance controls that the original 5 pin didn’t.

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Despite my successful cold start this morning, I will get a spare control module. Comparing diff ones. I want a black case as I believe it should have been originally. Other than that doesn.t matter too much. Biggest functional diff is some are supposed to be better at high rpm . Not really an issue for me.

Looks like 4 vs 5 pin not a secret anymore. Hardly any 5 pins available. Guess most are only making 4's since they work for either.

This is from Spectra:
4 Pin module The replacement module you have purchased is equipped with 4 pins. Chrysler production modules now have 4 pins compared to the 5 pin original module and is the current application design for your vehicle.

Similar info from BWD:
5-pin vs. 4-pin: All Replacement modules for Chrysler applications have 4-pin connectors. Early O.E. modules had 5 pins while current Chrysler production also has 4 pins. THe New 4pin modules are correct replacements for both O.E. types (except Dodge Trucks with heavy duty emissions cycle carburetor with electronically controlled vacuum kicker).