Well, I finally got most of the rest of the stuff out of my gas tank. I found that the biggest part of everything moving around the tank was the remainder of my sending unit float, which had somehow deteriorated. After it and a little more powdered rust came out with a little gas, when I flipped the tank over I couldn't hear anything else move around so I decided to put the tank back in. So I put the sending unit back in, and the tank is back in now, hooked up, and partly full of gas. My question now is: should I put some fuel treatment in just in case I didn't get all of the water and all that out?