I don't know the particulars of your framework.
However, my gut feel would be that the main document to amend would be the contracts that you enter into under the framework to incorporate the ECI supplement wording prior to your directors signing it or starting work under it.
You may also need to amend the Framework Agreement to reflect this, but it could quite literally be adding in a statement to say that the Parties agree that the ECI clauses can be used for an individual contract.
However, my gut feel would be that the main document to amend would be the contracts that you enter into under the framework to incorporate the ECI supplement wording prior to your directors signing it or starting work under it.
You may also need to amend the Framework Agreement to reflect this, but it could quite literally be adding in a statement to say that the Parties agree that the ECI clauses can be used for an individual contract.