It's the exact same muffler as pictured below on the 42dd exhaust. You do what they did and you're good. Pretty much you cut most of the piping off that's on the muffler then take (2) 90' 2.5" mandrel bent pipes and cut them to size, weld them up to the tips & muffler. Use a combination of a 90' & 45' 3" bend to make the turn. Any muffler shop could do this easily if I can do it in my garage on the floor.
I've done setups identical to this one before - this time I was just planning on doing it with stainless steel instead of aluminum so it could hold up to the elements in NY.