I had the same issue when I got my diffuser.
you can loosen the clamps where the muffler connecting pipes connect to the X-Pipe and pull it out towards the rear. It's a bit of a PIA, I had to use a pipe wrench to get it to loosen up.
11' E92 M3 Space Grey | DCT | ESS VT2- 625 | Gintani Race (valved) + Quad Res Catless X-Pipe | KW Sleeve's | GC Camber Plates|Arkym Diffuser | Vorsteiner VRS Lip | P3 Boost Guage | Stud Conversion
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