Existing Cluster
For an already onboarded cluster in KUBE+ the signer component can be enabled via modifying the deployment configuration and executing the updated installation command at your cluster.
Refer to Modifying Feature Gates of Cluster for the steps on how to add (or) delete feature gates to an existing deployment.
Note: While generating the modifying the deployment configuration
select the Feature gate Enable mTLS Certificates for Service Mesh which
enables AppViewX Signer as a part of the deployment.