Nitewolf

Hey guys, first off I want to say i'm sorry if this question has been asked before, I searched a little bit but couldn't find anything. I have a '02 F-150 Supercrew with the 5.4. I recently put 2.5" dual in - dual out exhaust with a flowmaster super 44 muffler. It sounds better than stock but nothing like what my old '92 sounded like.
I did some research on my truck and found out that it's a California truck and has 4 cats. 2 front and 2 rear. Now the 2 rear have o2 sensors in them while the 2 front does not (goin off of what the shop told me, i've yet to crawl under there). Is there any way to all or 1 of these cats without throwing a TC? I've had my old muffler shop put the o2 sensors back in normal exhaust pipe somehow and it ran perfect. Please let me know, thank you very much for all your inputs and I appreciate your time.

By the way I currently live in Tennessee and there is no emission testing here so I don't need to worry about that.