i do not have an 01 paul.
i have an 04 black on black ZED with
-ECS supercharger kit (paxton novi 2000)
-American Racing headers 1 7/8" headers
-American Racing long tubes 3" with no cats
-B&B bullets
-Textrilla twin disc 6 puck
-ECS custom diff brace
wheels and other goodies blah etc etc etc
i have no codes. they turn off the rear o2 and u are able to fail 2 parameters i beileve and still pass.