Belt is routed correctly. Routed according to this diagram on the tensioner replacement page...

https://www.pelicanparts.com/techarticles/Mercedes-W124/30-ENGINE-Drive_Belt_Tensioner_Replacement/30-ENGINE-Drive_Belt_Tensioner_Replacement.htm

Already checked that and made sure I didn't have a long belt. I can swing the adjuster with the belt off. It can swing enough to actually HIT the water pump pulley with the adjuster backed way off. The problem is that when I do get the belt on and try to adjust, the idler pulley is not being pushed far enough away to properly tension the belt. I am thinking the rubber inside the tensioner is deformed. It's probably the original tensioner.