Check out vance and hines site. Look up Big Radius 2 into 1 for 2011 Dyna p/n 28003. Go to install instructions. I have what's listed there for the install.
Vance and Hines p/n 28003 (2006-2011) Dyna has 18mm o2 Sensor Ports
And that is a good point made, at this point, it truly is a bonus but is there a mounting bracket included?