Updated

lol like the picture

How to Change yields of this mod:

c:\Users\Admin\Appdata\Roaming\MedievalEngineers\Mods

in there you will see my mod file which will be called 1229113097.sbm

Right click it and hit extract to "1229113097"

Rename this folder to what you want your mod to be called.

Open the mod folder and go to Data\Worldinteraction\Mining

Open the minning folder in a text or notepad program. There you will see many entires looking like this:

<Entry VoxelMaterial="IronOre_RegularYield" Volume="256">
<MinedItem Type="InventoryItem" Subtype="StoneLarge" Amount="1" />
<MinedItem Type="InventoryItem" Subtype="OreIron" Amount="1" />
</Entry>

Anywhere you see

Subtype="StoneLarge" Amount="1" change the number to what ever you want one yield to be.

I usually do a Ctrl + F and do a search for StoneLarge to find them all quick.

Save the file.