I took the cats off my slp x pipe and replaced them with some straight piping. Everything slipped together fine but because there are no relief cuts in the part where the pipe overlaps it's leaking. The front of the cats goes over the piping and it has those zigzag cuts in it so it will squeeze up tight. The pipng I put in place of them is just being squeezed by the clamp and bowing out at the end causing a leak. How or what could I use to put cuts in the pipes so it will all go together tight again?