We use Mil Eliminators to correct the o2 sensors.I think that putting the engine inside the car is the job I most fear, because I always have some screws left over and things like that.
The headers are very good looking. and I see that you have the lambda probe connected, since you do not have a previous catalyst, what solution have you given so that you do not have a poor oxygen reading?
Looking for information from the Ford Taurus I've seen the latest version of the Duratec, the 3.7, does anyone know if you can get into the Cougar?
I see that a lot has been sold out there in F150 and many cars
Something like this: https://www.fswerks.com/products/oxygen-sensor-mil-eliminators-ford-focus-duratec-2003-2011
The 3.7 is an entirely different engine. They have similarities but it would have to be a 100% custom install if someone wanted to try it.