i did it on mine, and i have passed smog 2 times, once with the 2.5 liter and once with the 3 liter. its way cheaper then buying the precats.

98 svt contour, magnaflows, sho shop intake, sho shop high flow cat, no pre cats, custom cougars short shifter, 3 liter hybird engine woo hoo im happy, and just added a dmd underdrive pulley.