First, the installation on my H2 was TOO bad but did take a while. It was actually harder to get the old ones off - GM heads have a habit of the nut breaking off in the rear. The headers fit really good with one exception. They seem a little longer and it makes the exhaust impact the skid grate under the vehicle. I had to add washers to lower the skid grate by about 1/2". The stock install left the vehicle with a vibration.
Fitment 
