how to manage the symbolic simplified rep?

Hi here,

I try to apply a best practice using the symbolic simplified rep.

I read in an old help topic book that is possible to customize the 3D symbol.

does someone know how to do it?

when editing the definition of a symbolic component, I have this windows, but almost all options are unaccessible:

my idea is to substitute the geometry of a component by it symbolic rep in a drawing view.

thank you,

R.