If you have Asset Portfolio Manager (APM) and CA client automation only then the integrations is already enabled if you use the same MDB..
IF you are using CA-SAM then you should use that as the integration for APM not the MDB..
When the CA-SAM integration enables then the Client Auto integration in the MDB is disabled.
Also remember that you need to set up Reconciliation rules in order to se the links for both SAM and Client Auto in APM.