Hi Bill,
I think that agent installations also have a assignment feature. It sounds like your agents are already installed - but for new agents coming online you might be interested in looking at the following settings (part of the silent install):
Deploy Agents - CA Release Automation - 6.5 - CA Technologies Documentation
nolio.agent.mapping.application=<Application to map the agent to>
nolio.agent.mapping.environment=<Environment to map the agent to>
nolio.agent.mapping.servertype=<Sever Type to map the agent to>
Kind regards,
Gregg