I have one roof that is above another, so the down spout on the top roof is pointing towards the gutter on the roof below. When it rains the water flows out of the upper down spout across the shingles and into the gutter below. I would like to save my shingles by having the water go from one spout to the other gutter without crossing the shingles. What can I attach to the upper gutter, to make the water will flow directly into the gutter below without wetting the shingles? Any advice and assistance as to where to buy the materials will be appreciated.(I have asked this same question at three hardware stores and no one had an answer. I also saw a segment about this same question on This Old house, but I can't recall what they used to solve the problem.)