Hi. Maybe someone can catch me up to speed on 40 scrapers. I just got mine home from Ohio and need to learn more about it. The small serial tag is missing from the top right hand side,it is hand stamped underneath but is so pitted I don,t think I,ll ever make it out. Is there a hand stamped number some where else. Also from what year to what year were they made, how many were ever made and does anyone have an idea to how many are actually left in the United States? I have more questions but better let it rest for now. Thanks for any input you might have.