Thanks all, for the comments, links etc -- I've gotten several replies
> from the people in this group via email.
> My KSU should be here tomorrow ... and the phones to follow shortly.
> There is a bunch of the 25 pair cable up in the attic of the building I
> work in; I even found one with a female connector on one end.
> Now I'm shopping for a good punchdown tool. Looks like it's going to be
> the most expensive part of this whole endeaveor (Phone: $45. KSU: $55.
> Punchdown tool: $65 - 75).
I'm reading this a while after you seem to have gotten enough info to get started, but ...
I have the full Bell "Key Systems Service Manual" and can provide some help if you run into a wall on your project. It contains wiring configurations for various uses of the Key System, and all the KTU, etc, schematics. Email me if you need something from it.
Don