I have recorded this guide for SIP Normalization on call manager and also have elaborated a little bit on how we use the Lua scripting.
A SIP Normalization script could really help the customer as a workaround or a permanent solution for issues related to calling and CLID.
Disclaimer:
Cisco TAC does NOT support SIP Normalization scripts. If the customer has already applied a script, TAC does NOT troubleshoot it. It is the customer's responsiblity to make it work.