my younger son found a ratchet in a parking lot a year or so ago. craftsman, but had clearly been driven over a bunch, when we went to take it back, this is what we found:
they had a cardboard box under the register for the return, they toss it in. they have a plastic tool box with the "warranty replacements", 1/2" and 1/4" on each side of the tray, and 3/8" in the bottom. if you ask nicely, they will let you paw through them looking for the replacement you want, as opposed to just passing you the first one that they lay their hands on.
i have not been able to find mention of the kits anywhere, it is likely that they dont support that at all anymore. (*sigh*) too bad . . . . . .