I understand what you are saying, but my point is this:
The EEC-IV uses certain systems and components that differ from the V system (IMRC to name one system). It would seem cheaper just to continue using EEC-IV systems on an engine for which they have been tried and tested (3.8L, just need to be reflashed for the Windstar, as it was also new that year), and standardize all systems for a new engine (EEC-V on the Duratech), rather than deal with 2 completely different systems on that engine (again, Duratech). Considering that, why not just put OBD-II on both vehicles. Both were new for 95, and required completely new wiring harnesses, so why not standardize right off the bat? To me, that would have made the most sense. The logistics of supporting the different wiring harnesses itself would seem, to me, to be cost prohibitive as far as switching engine management systems mid-stream, since they had to know a good deal ahead of time that OBD-II was a requirement for 96+. They already had the EEC-IV system in place for the Windstar in 95 (from other vehicles using it, namely the Taurus, on which platform the Windstar is based).
Not trying to argue with you, it's just that the logistics of it all doesn't make economic sense to me.
