I am not sure on the California models, but on the 49 state models; starting in 2010 the headpipes of all the dressers started coming with catalytic converters. As you are looking at the right side of the bike, look down underneath and slightly in front of the passenger footboard. There is a section where the 2 headpipes join together and that is where the cat is located. It is substantially larger than any other section of the pipe(s). In order to remove it, I simply cut a section about 10" X 7" out of the backside of the headpipes and carefully pried it out(the cat is literally attached to the inside of the entire pipe!). I used a sawzall to cut the cat in half and took my time with a couple of chisels and screwdrivers and peeled it out a little bit at a time. Next I used an air die grinder to remove the left over pieces that were stuck all over inside the pipe. Then you use a MIG welder and weld the cut out section back into the back of the headpipe. Grind everything smooth and you can barely tell that the exhaust has been touched. The really nice thing is that the bike will sound a LOT better and if an overzealous cop stops you, you can show him your stock HD mufflers are still on the bike. If you are in a state where you think they will do emissions testing on your bike, I would think twice about removing the cat. If not, it is one of the cheapest mods you can do to get a bit more performance and sound out of a dresser.