Scaling the decal after placing it on the mesh

Is there any way to size up the decal after I place it on my mesh?
After placing the decal I have the object of the decal, but the problem is that scale property is read-only. I want to size up the decal after palcing it on the mesh, but also to change it’s position if possible.
The code is very similar to this, the think I tried is finding the id of the object and changing it’s scale property, but it is read-only, then I was experimenting with some three js function but it doesnt work on already placed decal:
sanbox
I am not exprerienced with three js so any help would be welcome, Thanks.
This is the object of the decal: