Here in GA we have emissions regulations (dyno testing) very simular to CA. & many cars fail due to CATS. This is somewhat a subjective subject as most newer cars in "good" tune could pass w/o cats. Older cars with CIS fuel systems like yours are the hardest to make pass when there is a problem. Have seen a few companies that will open up your exhaust system & install a new "BRICK". But I would go for option 5 & have the old pre-cats saved from old system & installed if needed.
MERCEDES BENZ MASTER GUILD TECHNICIAN
ASE MASTER TECHNICIAN
27 YEARS DEALER M.B. Shopforeman
190E 2.3 ITS RACECAR
1986 190E 16V
[This message has been edited by M.B.DOC (edited 05-30-2000).]