Making a mold. Answered

I am trying to make a fascia panel for a car. In order to do that I need to make a cast of one of the voids in a panel, from a vehicle console, since it can't be measured easily. I want to make the cast so that I can then make an accurate template from which I can make the panel I need.

I am looking for a material that is non-destructive to the plastic panel that contains the void. That will create a rigid solid replica of the void.

I know nothing about making molds and casts.

Thanks in advance.