97 GMC Sierra factory 5.0L exhaust uses a small down pipes with O2 sensors in each bank, then into a Y pipe with a pre cat O2 and after cat O2 for a total of 4 sensors. Truck has a 383 with mid length headers, 3" to 2.5" header collectors with O2 bungs for each bank. Head pipes will be 2.5" duals into a Jones Full Bore 2.5" dual in/out with dual 2.5" tail pipes. I have a 411 PMC to swap and I have HP Tuners that I have not used yet, so there will be a learning curve. I understand that the pre cat sensor in the Y pipe is to read both banks, and after cat is to read if its doing its job. Is the pre cat sensor actually needed since it has one for each bank? How can I disable the reading in HP Tuners for those two sensors? Trying to learn. Thanks.