Adding iSCSI to Rancher Deployed VMWare K8 nodes

I am utilizing Rancher 2.0.6 to deploy and manage K8 clusters on VMWare Infrastructure. The templates use the standard VSphere RancherOS image ( I am attempting to get Longhorn running on the K8 cluster but the iSCSI support is missing.

How can I go about enabling the iSCSI modules and support on RancherOS at node deploy time?