O2 sensor location?

[WBILB]

I have FFR 4 into 4 headers and Gas N side pipes. Considering the Atomic FI setup and was curious if any one is running the that set up and how you like it. Wondering exactly where in the exhaust system you placed the O2 sensor?
Thanks in advance
Bill

[edwardb]

Lots of threads on this question. Here are a few.

https://thefactoryfiveforum.com/showthread.php?28175-O2-Sensor-Placement

https://thefactoryfiveforum.com/showthread.php?29783-Where-Did-You-Put-Your-Roadster-O2-Sensor-Bung

https://thefactoryfiveforum.com/showthread.php?1678-Oxygen-Sensor-Location