Zoom in close enough that you can see and pick the end grip. Don't release the mouse button when you click on the end grip, instead move the end of the grid or level off of the screen (as if you were trying to drag it 6" off of your monitor). When you have moved the end grip off of the screen THEN release the mouse. Revit will not register the release of the mouse and will allow you to move the end grip while panning AND zooming to the position you want the end grip to be. Once you are in the new location do one click of the mouse and Revit will place the end at that point. The same rule applies to any objects you want to pull by its grips. Walls, line based families, repeating details, etc...