Thanks to Mike W. over at Another Gun Blog, I now have a coincidentally useful link concerning the construction of AR-15s, the parts one needs, and the names/details one should look for. Granted, the author of the forum post is approaching it from a police duty rifle standpoint, but that certainly is not a bad place to start. If anyone has anything to add, feel free!
Good and very thorough link! Here’s the CalGuns link to various lowers, the manufacturers, and the small differences. http://www.calguns.net/calgunforum/showthread.php?t=50947
The lower I have. Everything else… well, some of it is in the mail (MIAD grip, magazines, and stock), but I still need a barrel (thanks for the idea, but I do not think that place is going to work out…), upper, and all of the little fiddly bits inside…