I've never understood how a lockplate could be cased without producing a potato chip but reading all whatever it is that I've read and haven't done led me to believe the bits and pieces were packed in there in a disassembled state. I saw a critique of recoloring on a gun which was alleged to have been torched that suggested that the colors (read heat eyes) were bogus because they were continuous across mating seams (say trigger plate and bar or lockplate and bar in the case of a LCS) and that that wouldn't occur if parts were heated separately, as,according to the unstated assumption, they would if the guns were cased by bone charcoal and heat in the time-honored and legitimate process. . . mumble, jumbo, jumble mumbo. Personally, I didn't think that indirect evidence of torching was necessary with that gun but it does make clear that some folks think that in the legitimate process(es) parts were packed in an unmarried state so to speak and might take exception to b. above. Course some folks are wrong some and a lot a lot and a few just a little bit so undoubtedly it might take a team of historians (and a book) to prove or disprove that the one true process has always been followed by everybody (without a clock and a pyrometer) now and forever, world without end, Amen.
Stamping parts with a serial instead of a generic part no. is understandable when and where parts are hand-fitted and one part fits but one gun but I don't see it as more necessary to a procedure for which parts that go together are together than it would be for many procedures (including repair) where they wouldn't. But I admire your confidence that you've seen it all.
jack
