Power steering pump belt tension

I had the power steering system rebuilt and have mounted the pump, but I am missing something when tightening the pump. There are three bolts 2 I can tighten down, but not the special one is which, only threaded on the last inch.

The way it is now it now it pivots on that bolt so I can't tighten the belt. What am I missing? Just a flat washer?

Also do a just use regular power steering fluid?

Here is a pre-rebuild pump with the bolt in question.

Steering pump.jpg

Steering pump.jpg
Author: Zymurgy