If you really can get your hands on a 2.5 Duratec before you pay for it, check the mains. Quite a few people have lost motors that way. Check the archives for discussions on: DMD, oil starvation, oil cooling, oil pan baffles.
Older OEM water pumps are garbage. There are a host of choices and much discussion on that one.
95s have an EEC-IV controller, and vacuum operated secondary intake manifold control (IMRC). 96+ is EEC-V and electrically controlled.
95 - 97 has an odd set of injectors on it (and is return fuel). 98 through sometime in 99 has a return fuel system, 99 and 00 are returnless (where a "smart pump" controls presure via the PCM). The fuel rails and injectors are different on the late model options, but both are a more common style of injector.
The SVT intake setup is better (obviously) and the later the parts you get, the better they are.
All 00 motors were bored slightly down to get under 2500cc (Euro gas guzzler tax).
After 2000, the Contour died, but the 2.5 Duratec lived on in the Cougar. There are also a Duratec here and a Duratec there in other Ford family of vehicles (both 2.5 and 3.0L).
