So I went to an exhaust shop to fit a silencer in the exhaust. I couldn't do it myself because the radius of the silencer is = to the radius of the exhaust. It needs to be a little smaller to fit in, so I hoped a shop could do it. They were unable to do so. The silencer came from Topspeed for the exhaust, so I dont know what to do. It's 4in, so I need a 3.8in silencer. Ideas?