Ray,
I don't remember my search words, but it was probably "oil pan ribs" based on your original post verbiage. Searching does become a bit of a art over time. And, some people just prefer the social conversational aspect of asking whatever comes to mind.
I can't imagine why the transmission type would affect the engine oil pan style. And, in that long thread, it is stated that the ribbed pan was released after W113 production was complete (or maybe as Dan says here right near the end of production), and it is the replacement pan now from M-B. So, I guess if you see one on a W113 you'd have to ask why a replacement was needed.