Set CID question

You need to create a context in extensions_custom.conf with an arbitrary name like this:

[from-pstn-preprocess]
exten =>  _./1234567890,1,Set(CALLERID(name)=NewName1)    ; all inbound calls matching cid number 1234567890
exten =>  _./9876543210,1,Set(CALLERID(name)=NewName2)    ; all inbound calls matching cid number 9876543210
;  additional set lines as required
exten =>  _.,1,NoOp(Entering user defined context from-pstn-preprocess in extensions_custom.conf)          ; Catch all other cases
exten =>  _.,n,goto(from-pstn,${EXTEN},1))

Then edit your trunk(s) and set the context to from-pstn-preprocess. You can set as many priority 1 lines as you want for each different CID number.