Tying to replace stone with another block, any help?

I've been trying to get the stone in one of my biomes to be replaced by another block. I have a procedure, but it doesn't seem to work, I'm new to things, and kind of stumped, any help would be greatly appreciated.https://imgur.com/a/876AEBA <here's a link to the procedure, I'm too big of an idiot to get it to imbed correctly. Sorry.