The only flanges that I know of (not sure what year SHO you got), are the two on the front. One that comes down off the y-pipe and connects to the intermediate pipe with two spring bolts and a donut gasket between them. I believe some SHO's had a flex pipe too with flanges on them. I don't think you can get the flanges (why is this word censored without the "s" on the end?), because the pipe its on is flared at the ends. So the pipe itself comes with the flanges on it.