pop the hood jack up the car look at stock exhaust manifold from the open hood point of view. Now crawl under the car and look at the exhaust manifold from under the car and notice where it bolts to the cat. If you cant figure out how to put it on after looking at in from the points of view that I just mentioned then it would be wise that you not work on your car. They are very simply to do just look at it and it will all come together. As far as the o2 sensor goes (the only forseen problem you should run into) unplug the o2 sensor at the harness and take the stock manifold off with hte 02 sensor still in it. With the manifold off the car take the o2 sensor off and put it in the new header.