New and confused. Very Confused Rought Idle and can't find Rear O2 Channel

[jrick]

Some background, I'm very new to this. I'm pretty much just trying to diagnose my truck at the moment and eventually tune something but 1st things 1st.
ECM does not have a tune.
(6.0L Vortec, 2012) Truck idles rough, but will come out of it if givin some throttle, basically its loading up. Lets just say this got the parts cannon and then some. basically I haven't replaced the MAP sensor yet, and thats about it. I'm Using MVPi3 and can't seem to figure out where to turn on the Channel for the Rear O2 sensors.... Lots of options but nothing seems to actually do anything, Also I have attached a log of the rough idle condition I'm gettings. If something stands out please let me know.. I mean its a mess... but if someone can look at it and give me some direction I would appreciate it.
thanks.

[SiriusC1024]

O2 sensor B2S1 isn't reading correctly. B1S1 is also acting strangely. I'd replace all of them, front and rear, with Denso sensors from rockauto.

[jrick]

O2 sensor B2S1 isn't reading correctly. B1S1 is also acting strangely. I'd replace all of them, front and rear, with Denso sensors from rockauto.

Just replaced all 4, 2 weeks ago with AcDelco's. I'm going to swap the 2 tomorros and see if the readings change.
Thank you for the reply