Z400 2023

I recently purchased the akrapovic headers for my 2023 z400. I already had the sc project CR-T slip on installed. I had problem when I went to install the akrapovic headers and realised the end of the header pipe is larger than the end of the sx project slip on. Does anyone know where I can get a mid pipe that would fit. I believe the header pipe is 51mm at the end. Not too sure about the slip on.