Installed my stainless ones a week ago. For me, best way was to carefully preassemble the whole exhaust, making sure all the pipes are fully seated. Wasn't too bad if you took your time on a soft surface (carpet) and slowly wiggle each side little by little. Then install the whole thing just like the way the stock one came off. It also helped to rotate the rear bracket/hanger off to the left side (when looking at the exhaust from the rear of the bike) so it clears as you're trying to fit the pipes onto the flanges on the heads. I also polished the whole exhaust before fitting with a scotchbrite pad to get rid of all the manufacturing blemishes and the uneven heat discoloration from the welding process, so it would look more even when it patinas up with heat.Just installed mine (Stainless Steel version). Kept the stock Akra dual cans, removed baffles, and valve delete. LOVING the sound now. There's more noise for sure, you can definitely hear me coming down the street but not offensively loud.
I will say, while the removal of OEM headers was super easy, getting the Arks to fit right, was a pain in the royal rear end! I tried starting piece by piece (first from the front to the mid section, and vise versa). Even with rubber mallet I could not get the darn thing aligned. The only way I was able to do it is pre-assemble everything, a set of second hands, and a few slams with a rubber mallet. When all was tighten up, the muffler aligned perfectly and the headers presented no leaks or rattle. Fitment is perfect.
*I will say that the center (cross) pipe towards the front is shifted a little more to the left as one spring is noticably stretching more than the other. But I could not feel an exhaust leak so I'll leave it as is.