Same as mot test emissions regs,they select from menu and do what machine tells them .
And don't forget the 1200.ppm HC reading,you can have low CO and high HC.
Cost : Little as possible.
Thanks : To those who by their generosity my build has progressed.
Its a handmade sports car not a flaming kit car !!!
If at first you dont succeed,avoid skydiving...
No parachute require to freefall,only if you want to do it twice.