Emergency CID Override

Is there a way to set a specific Caller ID for all emergency calls? I want to have a seperate caller ID for outgoing calls than emergency calls. My VOIP.ms trunk requires the DID number to be sent for emergency calls for e911 to work. I am running FreePBX


set the emergency CID in the extension, create an emergency route checked as such, and the emergency callerid will be used if present for any call going down that route.