If you need to do paging on the X-16, there is no paging port, you must use a Viking 2000A (or something else I don't know about that could work too but the 2000A provides talk voltage).

I have some new 2000A units that got screwed to the wall then not used. Bummer. If anyone needs one, happy to help you with the unit and setting it up over the phone.

Thanks, Bracha