I got my American Racing headers today. Now I have a dilemma. When I installed my AEM wideband gauge, I followed along with some advice and installed the sensor downstream of the cat on the driver side and had the downstream sensors tuned out. But it seems that my readings aren't accurate since they fluctuate wildly, and the instructions say it should be installed upstream. So I have 3 choices- install it the way it is now, install a bung upstream and plug the downstream bungs or install a bung upstream, buy new downstream sensors and have them turned on in the tune. Any suggestions?