Bought one with about that much delam. Perhaps some more. Repaired it successfully, but it was a great deal of work. I can share my methods if interested. But I want to mention the aluminium molding is terribly in in adaquate to maintain watertight joint (intersection of vertical and horizontal surfaces) I have recently seen custom made aluminium molding to resolve this issue. It is what needs to be done to permenently fix it. In my case I caulked the daylights out of that area and put Eternabond under the molding, because I could not get wider stuff.