Its pretty easy if you want to. there is one screw hole through the insert and there is a matching hole on the inside of the exhaust.
put the insert in so the metal end goes down in first, match up the screw holes, and your done.
well I installed the db insert,bike is a lot quieter but the midrange power is much improved, bike pulls hard up to redline ,if you got one try it .also it was not easy ,did not slip right in,so I put it in the freezer took bike for long ride and got good and hot then it slipped right in.