so i ordered two new front oxygen sensors. only problem? the little "nubs" or "ears" dont match the old ones at all. not to mention the old ones where blue and these are green. but heres the thing, the rear O2 sensors are green and the nubs match perfect. which leads me to believe that the dumb ****s at rockauto sent me the wrong motherfucking sensors! so my question is, can i just cut the little ears off and use them in the front? whats the difference between the O2 sensors in the front and rear?