I have been fighting with my upstream o2 sensors bought 2 that were supposed to interchange between up and downstream (lesson learned double check first) and they were downstream only tried splicing the old connectors in and no luck I really am not wanting to put over $100 a sensor into this thing its a winter rat and destined to be a off road rig come spring I noticed the 4.7 is the same connector wire color etc but says it wont work in the 4.0? are they actually interchangeable and it says not so you pay the expensive price or will it actually not work?