Thanks Terry! I don't know what I want to write this off as, but I think I know how I'm going to proceed for now.
I found just 3 half circle retainers from when I tore down the engine, and one full one. Like Terry said, I believe the full one sits NEXT to the large bearing. The other one is definitely not grooved because there is no recess cut for a half ring in either of the cases. So either these are a terribly odd cases, or the fiche is wrong. Either way, I think it will work out fine if I put it back together using Option A above. Pix to come as soon as I'm done with it.
In the meantime, I finally found the newer C2-C5 set. Now that I've taken a closer look, they don't really look that much different when it comes to dog wear, but then again, this is my first time so what do I know. Can anyone tell if the used set is any worse? The only difference to my untrained eye is that the parkerizing has been blasted off the newer set. Its also missing an oiling hole, and the stamping is different. Thoughts? Should I reuse my old ones and save the clean set for someone else?
C2?