I have the tti setup including the headers..... the first time I assembled them and put them up to the headers ...the distance was too wide to go on the headers .... I put my floor jack under the x-pipe and raised them up and bolted the one side to the header and then pushed the elbows upward where the met the x-pipe and and that narrowed the space where they lined up to the header adaptors. Did not need to cut them.