Marti,
Some things you should be aware of.
1) Be careful reattaching the door grips or handles; as you see they fit with two phillips-head screws. Despite being quite careful one of mine has stripped its threads and I have yet to devise the proper repairs for it. I believe these screws are going into a zinc or aluminum castiing which is quite soft.
2) The pieces you found on the bottom of the door are the guide jaws. These rattle around and cause havoc which is why you are in there in the first place.
3) In my opinion, a well-repaired guide jaw is preferable to the glass-welting "repair kit" that Bud's Benz has sold you. I installed this in my drivers door and it will be coming out. The problem is it does not provide enough support to hold the glass, particulartly in the glass "up" position. My window can move back and forth quite a bit; this is not good. My passenger door glass is quite rigid the way it is supposed to be. Others have found this Bud's kit to be fine. Not for me.
I had a lot of rattleing around in my door and thought that the problem was the same as yours; that's what everyone told me. That was NOT the problem. The problem on my car was the bottom of the window winding mechanism, when the window was all the way down, was contacting the bottom of the door. This "metal on metal" contact resulted in a terrible rattle. As I mostly drive the car in the summer with the windows down I never thought to raise it to see if that had anything to do with the noise.