I am trying to replace the O2 sensor on my 2005 Honda Civic LX 1.7L, and I need to make sure I am buying the right part. The O2 sensor I need to replace is right in front of you when you pop the hood. (Wires connected to the computer system?) I need to verify if this part is before or after the cadalytic converter. (Upstream? Or downstream? As some part stores reference). Thanks!