yes thats correct. to do a full 3l in an eo you will need the npg fuel rail adaptor if you want to use the correct injectors, as well as injector harness adaptors. you can use your stock injectors but they are on the edge of sufficent as well as the wrong spray pattern. you will also need a tune, no way around that on a full 3l. a full 3l tends to cost a little more because of the extra parts needed. if you're looking to do it on the cheaper side a ported 3l might be better for you, it doesnt require the fuel rail adaptor or a tune right away, and looks stock too.
--current cars: 1998 contour svt # 0165, 2009 mercury mariner premiere
--past cars: 1996 contour se, too many mods to list!!, 1999 silfro svt, 1999 tropic green svt, and tooooooooo many others to list.