For those who are interested in making your own x-pipe, you might use my drawing from which i made my own midpipe replacement.
I did use the materials which we had available in our workshop. It doesn't have to be exactly the same as long you keep the main dimensions in mind.

Performance so far so good, took me a few days to get used to the more brutal sound and car behaviour. Just a slight drone at 1500 RPM initially but not noticeable anymore at the moment. Car runs great and pulls to higher RPM's on full throttle. Feels like the car has more benefit from the Velocity Pulley and ECU tune i did in the beginning this year.

 

Good work.
This is going to be quite loud and a little droney because you have taken both the central muffler and resonator out of the system. The resonator is needed to eliminate drone, when I had an H-pipe installed in my old XFR it was in place of the central muffler but I left the resonator in place.