Bill,

Apologies for the late response; I hadn't set reply notification.

I don't think it's worth me trying to track down full manuals and order in that case. Perhaps somebody could give me a quick overview of the basic 1A2 wiring for reference.

Obviously each line requires tip/ring pair, and I think I've gleaned from other posts that a second pair labeled A/A1 is used as the holding circuit through an extra set of hookswitch contacts. Presumably a 3rd pair for the line lamp, although something about lamp returns being commoned in some cases?