Several flags, per station. SYSTEM/PHONE-RELATED INFORMATION/FLAGS. Turn on OUTSIDE PARTY CALL INFO HAS PRIORITY, EXPANDED CO CALL INFO ON DISPLAY, DISPLAY OUTSIDE PARTY NAME. You can view HELP to understand how each of these works. And this assumes that you are already getting CLID on the trunks, which is default on PRI or SIP but needs to be turned on in SERVICE TYPE on loop start trunks.