I have read the frequent questions and answers on how to connect to the Viking PA 2A paging system it seems unclear To me. I need to install paging and as well as loud ringing does anybody know the best way to do this. Using the Viking paging system. I know there is a auxiliary ringing a source on the block. but the Viking uses contact closures for ringing. And I need to be able to turn the ringer on and off from SET 21 so do I use the night service what type of programming do I need to do please give step-by-step thank you very much.