Creating a custom class and iso symbol for a piping component

We have a few different types of piping components that we would like to add to our model. These components are i.e. an Air release valve station or a service water outlet, the standard details for the assemblies comes from a standard drawing so no need to model the whole assembly every time. The idea is to use the place component from cell tool. For creating the cell I did follow the same workflow as this link:

https://communities.bentley.com/products/plant/w/plant_design_and_engineering__wiki/18502/how-to-create-custom-components-from-cell

 

The only difference is that in the Custom Piping Component Builder I did not want to use inline component as a component type. I've used this before with great success, however for this instance I do not want a box to be displayed in the iso’s but something a bit more representative.

Question: How do you create a class that can be used in the Custom Piping Component Builder as a component type that will in turn use a custom isometric graphic? What do I need to do to create such a graphic?

Thank you in advance for the help