[COFF] Dataphone 300 Info/Docs?

[segaloco via COFF]

I've got an exciting piece of hardware to pair with the VT100 I recently got, a Western Electric Dataphone 300.  The various status lights and tests seem to work, and the necessary cabling is in place as far as the unit is concerned.  However, it did not come with the accompanying telephone.  I believe but can't verify yet that the expected telephone is or resembles a *565HK(M) series telephone, the ones with one red and five clear buttons along the bottom, otherwise resembling a standard WECo telephone.

Pictured: http://www.classicrotaryphones.com/forum/index.php?action=dlattach;attach=439223;image

Thus far I've found myself confused on the wiring expectations.  There is a power line going into a small DC brick, one DB-25 port on the back terminating in a female 25-pair amphenol cable, and another DB-25 port with a ribbon extension plugged in.  My assumptions thus far have been the amphenol plugs into a *565HK(M) or similar series telephone and the DB-25 then plugs into the serial interface of whichever end of the connection it represents.  However, while this is all fine and dandy, it's missing one important part...a connection to the outside world.  I've found no documentation describing this yet, although a few pictures from auctions that included a telephone seemed to have a standard telephone cable also coming out of the back of the telephone terminating in either a 6 or 8-conductor modular plug.  The pictures were too low-res to tell which.

Would anyone happen to know anything concrete about the wiring situation with these, or some documentation hints, as I've tried some general web searches for documentation concerning Dataphone 300 and the 103J Data Set configuration and haven't turned up wiring-specific information.  If nothing else I might just tap different places on the network block of the 2565HKM I've got plugged into it and see if anything resembling a telephone signal pops up when running some serial noise in at an appropriate baud.  My fear is that the wiring differences extend beyond the tap to the CO/PBX line and that there are different wiring expectations in the 25-pair as well, this and my other appropriate telephone are both 1A2 wired I believe, still working on that KSU...

Any help is much appreciated, lotsa little details in these sorts of things, but once I get it working I intend to do some documentation and teardown photos.  I don't want to take it apart yet and run the risk of doing something irreversible.  I want to make sure it gets a chance to serve up some serial chit chat as weird telephone noises.

- Matt G.