This works great for my 2003 Tib GT, it may or may not work for you. Costs about $3.95/pack for non-foulers.

You can make these yourself very easily instead of buying them "pre-made".

Go to the parts store, get 2 packs of spark plug non-fouler # 42009 or # 42002.

Get a 1/2" drill bit, drill out 2 of the non-foulers so the O2 sensor will fit in it.

Screw 1 of the drilled non-foulers into one of the not drilled non-foulers. (I used a little gasket maker to seal it)

Screw in your 1st lower O2 into the non-foulers, ziptie it out of the way (there is not enough clearance for even 1 non-fouler to screw into the header bung of my SSA headers but other headers you have room to screw it in your bung)

Screw in your 2nd lower O2 into the non-foulers, install in 2nd rear header bung.

Clear your CEL and your done, problem solved.