Been working on this w/ a spreadsheet. Trying to get some decently firm ideas conc. casting dates as related to assembly dates and then diode dates as related to same. Most alternators we see have positive diode dates from the same lot and the negative will also be the same. There are others that have had wildly spread dates. As far as the top three stamped numbers my money is on shift, plant, and line. Thinking that somebody had to be accountable if a bunch of "duds" came back. Still trying to find what NW stands for on some of the alternator and starter castings. KCP = Kokomo Casting Plant and they came us with some real crap toward the end of the "roundback" era.