How to remove items from the Navigator in Billing Management External User

Summary:

We are implementing Billing Management for external customers to use. When the external user logs into Bill Management a Subscription Tab is visible as is a custom dashboard. There is no way to remove this via a custom version of the external bill mgt role as that role has no embedded privileges.

I have been able to use a sandbox to remove the tab and dashboard using a Sandbox, however I had to log in as an external user with Application Implementation Consultant role.

In live I wont be able to do this as I am not a customer and the Production environment has single sign on and MFA.