Do the cats. Not just for the sake of inspection and the cops, but to stick it in the azz of all the liberal, soy-eating loudmouth know-it-all hippies who love to piss and moan about how our passion for motorsports is killing mother earth, maaaaaaan.
When I had to put a new cat on the Jeep, I went with a Dynomax high flow 3-way cat that set me back about $60. And I'd do it again. Some enthusiasts can be our own worst enemies by skating on things like cats, mufflers, proper lighting, etc, and then they sit there and blame everyone else for a problem they created. If the car is getting driven anywhere besides the track, make sure it's safe and not spewing toxins in the air. You'll feel that much better the next time some smug, sandal-wearing Smart Car driving hippie tries to chastise your choice of transportation.
