Only alow to select Part "Assembly" instead of all Parts like "Component", "Assembly", "Material",...

Hello everyone,

i am new to Aras Innovator (I am using Version 12.0 SP9 Build: 24090).

I have created several Parts (Components and Assemblys) and a new ItemType "Test". I have modified the "View" of the ItemType "Test" to select different Parts. Like this:

Now i want to modify the selection so that it is only possible to select Parts with the Type "Assembly". Something like this:

But the "normal" user shouldn't be allowed to select a Component and only Assemblys.

Do you know how to do this?
Thanks in advance.

Best regards
Thomas