4wire vs 6wire step mtrs also Taig mill S&D conversion

I recently bought a "preowned" Taig CNC mill and I've
already decided I want to convert it to Step & Direction
for a number of reasons (which I won't go into here).
I would really appreciate some advice/comment from
those of you out there who have experience in stepper
drive systems. I know how to use them, and basically
how they work, but some of the electrical requirements
and connection considerations I'm a bit weak on.

Q1: Have any of you other Taig CNC mill owners out there
converted your system from the LAMDA phase controller to
Step & Direction and what was your approach. Did you
use any part of the LAMDA controller (ex: the power
supply, case and connectors) or did you just set it
aside and put in a new front end?

Q2: I am looking at Stepperworld's FET-3 product which
looks great for what I want to do (I think).

http://209.41.165.153/stepper/fet3.htm

has anyone else used this board with the Taig motors
which are 6 wire steppers from Shinana Kenshi Co. Ltd. (SKC)
model # SST57D5101 / 1.8 deg/step / 9.2v / 1.0A / 200 oz/in
holding torque with the following wiring which I assume
makes them unipolar:

Phase 1 ------+
|
+------Common---(13)
|
Phase 3 ------+

Phase 2 ------+
|
+------Common---(24)
|
Phase 4 ------+

Noting that they are 6 wire motors and assuming they are
unipolar is an integral part of my befuddlement and the
questions that follow.

(about here is where the waters begin to close over my head :-)

Q3: Can I use my PacSci 6410 drivers?

Another way I can go in doing the conversion to S&D is to
use a bank of (4) Pacific Scientific 6410 drivers I have all
powered up/wired up/ and ready to go (this has the advantage
of letting me add a rotary "A" axis later and keep everything
the same). I am using the 6410's to drive steppers which I am
installing on my Taig lathe (these are 4 wire motors and work
just fine). My question is can I treat the Taig motors
as (4) wire motors by just tying both commons together back
at the 6410. If you want to look at the 6410 reference the
.pdf is part way down the page here:

http://www.pacsci.com/support/downloads.html#6400

In the .pdf manual for the 6410 they describe driving 4 wire motors
and 8 wire motors but not 6 wire motors. Is this a problem? The
voltage supplied to the 6410's is 24v and I believe the LAMDA
phase controller which comes with the Taig also is 24v. The
thing that gives me some pause is that the cable from the Taig
motors back to the LAMDA box have the two commons on separate
pins ... I gotta believe that's for a reason otherwise I would
have tied them together and plugged um into the 6410 already
(being basically the "plug it in and scrap the melted plastic
up later sort of guy that I am")

Sorry this is so long but it seems to me if you're going to ask
a question and expect a reasonable answer you ought to provide
as much info as possible.

Thanks for any help, tips, comments, suggestions in advance. You
may either respond here or email me directly.

Ken Jenkins
kjenkins@....