You have to loosen the bolt in the center of the idker pulley before you turn the tension adjusting bolt on top of the idler pulley bracket.

I use the breaker bar on the dside frame rail method and bump the starter to loosen the crankshaft bolt. As a true rednek, I use a sledge hammer to retighten the crank bolt, but I do not recommend this method due to liability concerns.

Not responsible for advice not taken...