I just picked up my White Bros pipe at the post office and noticed that there is a big wide eyelet on top of the aluminum can. The WR 400 mounting instructions say "install stock rubber grommet into mounting bracket on silencer." My stock pipe has a skinny flat metal flange that bolts to the frame. Are the US pipes set up differently? I haven't gone down to line it up on the bike yet, but it looks like I'm gonna need a longer bolt, rubber and collar. Anybody run into this?