When the mail came today there was a package from Numrich Arms; the GEW98 rear sight assembly that I ordered last week. All looks good, no rust or wear out of the ordinary. One little problem, though. The sight assembly is attached to a sight base which needs to be soldered onto the barrel. The barrel of my 98 already has the base on it. I need to remover the sight itself from the base that it came with and place it on the sight base already on my rifle. How do I accomplish this? Thanks.