*Edit* Terry beat me to it! Man he's fast!
My deck is a little bit newer model I think, but just for clarification, this is what setup I think Terry is talking about.
The newer idler setup uses a long bolt that comes through a nylon bushing in a slot on the "bar". This pic is from standing behind the deck, as opposed to in front of yours:

Here's a closer pic of the nylock bolt that holds the spring in place. Forgive the custom silencer (hose pipe/zip tie combo) and krud...

Your deck appears to have an older setup, without the slots. I've got an older one outside in the barn, but I'm not certain it is just like yours or not. Unless someone beats me to it, or the one in the barn is the same, I'll get you some pics tomorrow.
Kevin