UltArc, some good news bad news for you.
Bad news, I don't think that a "Kamm" will do anything other than hurt your cars aerodynamics.
Good news, Your car is pretty dern aerodynamic to begin with, and you don't have to build a Kamm.
Here's why I say this.
First, keep in mind the Kamm is meant to remedy a hideous aerodynamic situation on a car which has lousy aerodynamics to begin with.
Uh..Yeah
Your Ford was designed by folks who wanted to make the car as aero as possible here in modern times. One of the key indicators of this is how close it already is to the Aero Template. I have it illustrated here with the newly minted "Faster template" and as you can see it is very close.
One of the main things to really get excited about with your cars aero is that there is a smooth arc from the base of your front window to the bottom of your rear glass. This my friend is Aero Gold. People put Kamms on their crappy aero cars hoping to come close to what you have to start with.
Ford has certainly tweaked the sides of your car to match the flow going over the top, if you screw with this, you'll certainly pay a price.
Bottom line is that your car has been optimized for what you have, short of redesigning the entire car to look like this,
all you can hope to achieve has already been done.
At least in the back. Do seriously consider a grill block if you have not put one on already.