Look like both downstream O2 sensors are done. I did SVTEdwardo's headers and he DOES have MIL's. I think that the O2 sensors are just done.
The reason his car reeks of gas is becuase it has ZERO catalytic converters. If you add a universal 3" cat (cos he has 3" piping) THEN it would get rid of the stench, and I think it would run better too, as the 3" exhaust he has on there is a little overkill. The addition of a cat will help by adding a restriciton to get the exhaust velocity back up to closer to where it needs to be.
