Ok i know that it is against the law in the USA to do this for emission control purposes.
Here in South Africa we dont have that strict laws on emission control.
What all must be done to ECM and or o2 sensors to avoid engine light coming on if the cat is removed
Is there a by pass procedure available for the down stream 02 sensor that avoids error codes
O2 Bung Extender
This is an O2 bung extender that can help with fitment in the downpipe tunnel. It is made from Stainless steel, has straight and a 90 degree bend so you have two options for the best fitment. The 90 degree extender angle is adjustable so it can fit in any position. Not for use on primary O2 sensor.
BNR, Trifecta, ZZP and Vermont Tuning are a few of the tune providers