Wrong sparkplug?

Hi guys,
I needed new sparkplugs for my '91 Chevrolet Caprice wagon and I got ACDELCO's R 43 S plugs from the store. I asked them if they were sure because Rockauto mentioned a different type of sparkplug. But did put in the wrong sparkplugs now? The ones that came out of my car were Acdelco CR 43 TS.
Is there much differences between these types of sparkplugs? And what's the worse that can happen if I drive with Acdelco R43S?
I must say, my car drives fine.

The "ts" stands for tapered seat. You need the tapered seat for the engine.