My kit gun airweight model doesn't have a matching s/n on the yoke and also under the grip it is only stamped with a "6", not the complete s/n of 61xx. The standard catalog of S&W says it should have all these matching serial numbers. I pretty sure the elderly lady I inherited this pistol from bought it new and never had any work done to it. Could the catalog be wrong? All the other s/n's match; barrel,butt,cylinder face,under the star.