s14 O2 sensor problems

[waitingroom]

i bought an s14 header on the cheap. go me. well anyways, i'm installing it and my car is transitional obd2, versus full obd2 in later years. My secondary o2 sensor was really small, as opposed to the o2 sensor hole on the header, which was standard size. So what did i do? jbweld. however, the exhaust system eventually popped the o2sensor out like a cork from a cork gun and demolished the sensor in the progress. So now is decision time. Some people have told me that the early s14s (not fully obd2 compliant ones) don't even really need the secondary o2 sensor for engine controll, it's just there to be transitionally compliant. If so, i guess i can just get a plug and plug the thing up, as it is rigged right now. However, if this isn't the case, and i could get better milage and power by using a secondary o2, can i use a later-year s14 one? will it work the same? will i need to mutilate my plug to use it? thanks a million guys.