The last step of the modeling is to set the value for the resistance in the circuit. This can be done by creating two InstanceSpecifications, one for the source and one for the resistor. Values are used for the amplitude of the source, and for the resistance of the resistor respectively. These InstanceSpecifications are then set as default values of the circuit source and the circuit resistor (see the image below).  

The Source and Resistor Instance Specifications with set default values.