Well i re-read the bently and it sounds like they say to tighten the pump down before adjusting the tension. But they use the word nut, not bolt. HMM!!
anyway, i looked at it for a long time and it didn't make sense that you'd losen the bolt to turn the spacer, so i went ahead and got a good wrench and gave it some eblow grease.
It moved, and i've managed a complete turn or two!
Its hard to tell becuase it moves so slow, but i'm pretty sure i've gotten some of the slack out.