What's the difference?

Guess I should explain why I'm asking. Back before I picked up the 318 I'm stuffing in to the Sedan I was snooping around on ebay. I ran across a guy selling (what I can only guess are) factory "seconds". He had a new chrome small block pan for way cheap. And since I had no idea if my motor had been sitting on the pan potentially crushing it, I figured it was a safe buy. I didn't realize there was a difference.

So now I have this brand new pan and no idea which small block it fits. If it turns out it's for a 360 then I'll pass it on to someone who can use it.