Ok, So when I bought my car it came with the dual exhaust already put in. The thing is the guys that sold it mentioned not having O2 sensors in the exhaust. I found these http://www.mustangtuning.com/stmilel.html and they turn off the light. If I'm not mistaken, the 97's and up have a lil thing called "Limp Mode" when the Service Engine Soon light is on. It cuts down HP because it doens't want you to put too much harm on it because of the light being on. With these it says it turns them off... and my friend who has a Cobra said his brother got MIL Eliminators for his Lightning that did not have O2 Sensors in it and that they worked out fine. Just checking to see if this would be a good choice, and it looks like a decent price from what I've seen. Also when If I were to put these in and the light goes off, that means that it comes out of the Limp Mode stage? Makes sense to me but I just figured I'd post it on here.