Most efficient way to deploy template to all members of a user defined group

• Want to deploy a template to all devices that are covered by a user-defined group. Currently the process  is something like: 

1) Return list of user-defined groups with groups/userDefinedGroups

2) Identify the group interested in and make a note of the group ID

3) Return list of devices within that group using devices/exportDevices

• Unfortunately this returns credentials and IP address but not the device ID. Therefore have to lookup the ID for each device based on the IP address which seems inefficient to me. 
• To deploy the template you need an array of device IDs and wondering if anyone can suggest a better way to retrieve the IDs for all devices within a user-defined group. 
• Running PI 3.1.5.

 Replace step 3 with data/Devices?.full=true&.group=/User%20Defined/MyGroup

 That will get you the devices you need, with their IDs, and without fetching credentials.