I thought I remembered reading somewhere that the front sights on Trappers were soldered until around serial no. 6,000,000, but I'm looking at some pics of Trappers in the mid-5 million range (5.3-5.6 million) that sure look like they're dovetailed. Am I mis-remembering, or wrong, or is there no real rule of thumb here (as is so often the case with firearms manufacturing)?