A system for handling various structural building components including a pick and stack-registry lug which is anchorable to the top of a building component for handling that component in either one, or both sequentially, of its two, pick and stack-registry functional modes, (b) a clamshell-style, releasably lockable clasp adapted to receive and close capturingly upon the lug under operational circumstances with the lug anchored to the top of a building component, and ready to function in its pick category of component-handling behavior, and (c) a guide socket includable in the base of a building component functional for camming, guided reception of a lug with the lug then functioning in its stack-registry mode of behavior to facilitate overhead stack registering of two building components in relation to the lowering of an overhead component onto the top of an underlying component whose top also has a lug anchored to it.