How do I get the two existing O2's out? I've only tried from the top for the passenger side O2. Its near impossible to get the wrench to turn more than a few degrees, and I can't get a breaker bar on it either. Any tips? Is it easer to go from the bottom?

If you've done your O2's how did you get at them? I do have an O2 sensor socket which makes things a lot easer...

 

I just use a regular wrench to pull mine. You'll have to go at them from the bottom.

 

Yea You got to go from underneath only way.

 

Same here. i used a wrench and it was still a pain. Its much easier now that i have headers.