Add a Metric QC box to the HLV-H seperate from the origional

For us lowly HLV and HLV-H owners that do not have the later
HLV-H-EM lathes, I was thinking about metric gearing again.
I have come to find, that the change gears on the HLV-H lathe
do not compound through the QC box like all other lathes,
rather they are a separate entity that does not go through
the QC box. You can assemble some change gears to create a
custom pitch, but you can not select variants of that pitch
through the QC box. So if you assemble gears to cut 10 tpi,
that does not change any other thread selections in the box.
So in the same way, if you assemble gears to cut a metric
pitch, since it does not compound through the box, you need
to construct a change gear combination for each pitch of
metric feed. Most of you with these lathes know this.

So my idea, having said all this, is I was thinking to set up
a gear train with metric transposing gears, and then add a
separate QC gear box. I was thinking a SouthBend QC box could
be had on ebay from someone parting out a lathe. Hook up this
box with the metric transposing gears, and drive it back into
the input gear stud on the Hardinge lathe. Yes you would have
to do the math for what ratio on the SB box equals which metric
pitch, but seems easy enough.

So to sum up, the lathe would have a separate QC box just for
metric, or whatever compounding gears you choose to put in
front of it. Does this sound crazy or genius? Again, I know
it is always a fine line.

--Doozer