Yeah I have seen it, but I doubt it would be workable on the Duratec Contour, seeing as how the injectors are tilted. If you added this extra piece to the bottom of the injectors, the fuel rail wouldn't bolt up to the LIM or even allow the bolt holes to line up anymore, plus they'd probably causes the injectors to interfere with the UIM.
If the injectors had separate fuel rails for left and right banks that bolt to the LIM in the same plane (lengthwise) of the injectors it would be possible.
But of course if you have enough time, money and desire, you could probably make it work on the Duratec if you wanted too.
http://www.holley.com/HiOctn/ProdLine/Products/NOS/NOSNS/NOSzle.html 
