[ultimateirving]

The o2 housing will be all finesse. You gotta switch nuts every little turn you can get and wiggle the housing as you go. It will only free up a small amount at a time until you get the nut all the way off the stud. Before you put it back on, I would smack That shit with a hammer a few times and give yourself a little more room. Depending on boost run the pluggs .028-.030

As for the Ecu only two things can be done. Hook up the chips to a prom reader and see what the tune is. Or take it to a dyno and run it with a good wide band and slowly turn up boost. It might be easy to just get a new tune I don't think I would trust it. Then again I'm a highly skeptical person