You have a V6 SOHV engine. Go to the Motorcraft engine web site and ensure the part number for the two replacement engines are the same. If they are, you're good to go. If different, it may involve electronic modifications to the engine or inclusion of different and/or various sensors. If there is a difference, you will have to find out why and what other modifications may have to be made to the 2004 electronic components.
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