Not a problem. You just go down to a licensed epa exhaust shop. They will do the test. When you pass they give you a certificate, they keep one copy and send it to the epa saying you passed. Thats it.
DO what ash advised me to do. Get a mufler made up that decreases the diameter and just with a normal muffler. Lowered my car from 111DB to 89DB to just pass. And when u get home. Chuck the cannon back on