Oh, yeah. That O2 is a bit lower. I could not see it behind the AC exchanger (I took mine out). Where did you read about that RPM band for lean burn? For example here is a guy who says 1800 to nearly 4000 (!) works:
http://ecomodder.com/forum/showthrea...tml#post473444
Just wondering... there is a lot of contradictory info out there!