!!! AC belt W126 560 SEL

[LandYaghtLover]

Ok, I really thought this would come up in search, so I must be doing something wrong.

I am replacing all my belts after the alt belt failed today. I have everything figured out except the AC belt. Its over the crank, then a tensioner looking thing then the AC.

So first question is if that arm with pulley it rides over is a tensioner? If so, mine is stuck it would seem. Although I have not used blunt force yet. Did not want to incase its not spring loaded tensioner.

And if its not a self-tansioner, is the bolt that seems to hold the arm in place the one to loosen? Again, did not use full force yet incase its not.