This is one of those parts that I'm supprised didn't get added to one of our major vendors list of "must haves". If WCF or someone else had done this about 10 years ago, i'm sure they would have made their money back by now. but with the DOHC motor falling out of popularity, it makes no sence to do it now.
I was able to find a bracket in the Jyard that worked. To this day I have no idea what it was off of and I still look for it when I visit even though I dn't have a DOHC motor any more.
I simply took the vanes out of the pump, sealed off the fluid port with a hardware store cap fitting. The screw off cap allows me to keep fluid in the pump for lubrication. It's run like that for over a year now with no problems. No idler pulley needed, no new belt needed.
Go to a junkyard and grab a power steering pump idler off of any vehicle that has a 3500 pushrod motor. When gm went to the electric power steering they also need to have an idler where the power steering pump was. So that is what they used. I just tapped my top hole of the stock 3.4 Dohc bracket to the threads of the factory 3500 bolt and screwed it in. It has worled so far and works fine with belt tension on it