Same as you Scooter did everything new shocks brake pads front and rear.Couldnt find a single problem with my frontend to account for the clunk and had mine while driving on certain roads. And in parking lots while backing up with wheels cranked it would clunk. So I got to digging and this is what I found and it was the problem. Believe me never would have thought of that.
Copy and past this address into your browsew and I think you will be plesently surprised. And if you go to discount gm parts .com you can pick up the set for $76.00 One thing you can do as well as test as shown is to take a shop towel or a wash cloth and put it across the pads where the hood weight rest on the hinge pad and if a single layer of cloth isn't enough double it. Unless it appears then just click on it. And let me know how it works out for you. You can just P/m me to let me know if that resolved it.

 

I had already installed the GM washers. Still there. My noise proved to be the passenger side rubber hood bumper not resting on the underside if the hood when closed. Adjusted that and noise all gone.

 

Meant to mention that glad to here you solved it. I bought the washer as well but the hinge had such bad ware that it was almost disintegrated after about three days.But any ways keep that gm discount parts in mind when ever you buy parts. I actually think the GM dealer goes to them as well every time I check the dealer for a part its usually just a bit higher then .com and the dealer always has to order the parts for my blazer there never have them handy. By the way have you seen the leak detector I built click on the Header Ultimate Automotive Leak Detector and there will be a drop down window there click on my home web page its just a U Tube video if you haven't seen it before.