[Mr. Luos]

Hook the O2 sims up to each of the rear O2's.
Or delete them from the computer all together like I did.

Hi-flow cats are great, but they don't do enough for the computer. They will throw a code.
I have the off-road headers, hi-flow cats, and y-pipe from SLP on my car. Well did. I had the O2's deleted from the computer not 3 days after the header install. I hate that light.
Personally, I am ditching the SLP's for Kooks. Not for performance, but SLP doesn't make a 1 7/8" primary header. Plus, a stainless header rules.