FIRST... it is a FEDERAL LAW!! ALL the states are required to meet the US Federal Emission Laws. !! However...
IF , for the track, you pull the cats, the O2 sensor 1 must be kept. the down stream O2 ( after the cat) is a choice.. SOME have just left it out ( secured up under the car) some have put it back in the system, some have added a 'simulator' to trick it .
Myself... I put the O2 back in the system, and periodically I get a CEL for 'inefficient cat' ( duh.. it isnt there..lol) I reset the light and motor on!!
Is this the answer you want?? Doubtful.. but others will chime in I am sure!
Just me..............................
Thumper