For members that experienced CEL code after they installed an aftermarket exhaust or headers, how did you fix the CEL warning code?

I got a Supersprint race exhaust, using Factory header and Cats. It been running fine till recently. Long story short, Supersprint of NA of NO help, other then said to maybe try a spark plug non fouler or washer to space out the O2 sensors. If regular washer does work, what type of washer should I buy?

I heard about using 02 bung but they are pretty thick .5 inch almost. If other member have any suggestion on what type to use to remove this annoying CEL error, please let me know. Matrix is installing my new suspension as well as putting the Supersprint exhaust back on next week. So hopefully got this figure out before I drop off the car for install next week.

Tks in advance

 

Do you have an update re your CEL situation?