Placement of inertia blocks in system

Good day everyone,

I am unsure of where to exactly place inertias for certain components in a system I'd like to simulate. The system is described by the image below:

Currently I have the model as this:

Irrespective of the values of the inertia, I am not sure whether I've used the correct inertia block and if it has been put in the correct place in the system.\

Any help is much appreciated. Thanks