Create an electrode from mold core

I am new to SW surface and feature creation.

I was looking thru mold design tutorials and couldn't find a valuable answer.

Here is my question:

I have a core and cavity from a mold, imported into SW.

My challenge is to create proper electrodes for making the ribs and shapes on the core/cavity parts.

Is there a simple way to achieve this?

Can this be done in part environment or assembly?

Attached is a simple example.

Someone please explain the step by step procedure to get that.

Thanks

JOHN

SolidworksPlastics And Mold Design