Monoset ID grinding attachment quill removal

I hope I used the right terminology in the title!

I have a Cincinnati #2 T&C with a ID grinding attachment, except it does not look like the one in the manual. Looking at pics online I found this:

CINCINNATI MONOSET INTERNAL GRINDING SPINDLE STK 13989D | eBay

So I would imagine mine is the Monoset ID attachment. The question now is this: It has a short shaft (quill?) sticking out on the business end with a small collet in the end. Again searching online trying to ID the collet, it would appear to be a DIE grinder collet which seems to be limited to 1/8" or 1/4" sizes.

It looks very similar to this:

Draper 27942 3mm Air Die Grinder Collet for 38147 & 2556 Air Die Grinder & Kit | Rapid Online

except that it is slightly shorter by not having the parallel section at the back.

This short shaft/quill (about 16mm dia) seems to be separate from the attachment spindle and I was wondering how to remove it as I think the best option would be to adapt a ER16 collet shank to fit in its place. The nut on the existing collet is left hand and the shank has two flats to hold with a spanner. The problem is holding the spindle as the other end has aluminum pulleys. Knowing if it is left or right hand will reduce the risk of damaging something.

An exploded diagram of this attachment would be great!

Chrystal,
You have identified the Monoset internal grinding spindle. The collets, in three sizes, were once offered by a shop in Denver...about $50.00 the set on Ebay. Do you have the driver? The spindle is driven from the main spindle to the internal spindle just behind the stone with a small belt.

Yes, I have the normal spindle on the machine also. The monoset has the pulleys on the other end of the unit, nothing behind the collet. I suspect the collet ended shaft should unscrew from the spindle as I found another pic of a monoset on this fourm that did not have that part installed. Question is how?

I had a look on eBay before but can't say I found the collets. Problem is it will most likely be imperial and I'm in metric country so it will limit my choice of mounted points hence the idea of the ER16.

So you're saying the normal spindle acts like an idler? How does one tension the belt then? I'll admit I haven't mounted my attachment yet to see how it will all works out, maybe it's obvious once I do.

Yay, I won!!

Removed the pulley which revealed two flats on the shaft, with some muscle and two wrenches I managed to remove the collet shaft!!

It has a taper on it (15.8 big end, 13.8mm small end with about 42mm between, same taper as Morse 2, just smaller gauge) and also left hand thread screw on the end.

So now I just need to test the taper and then I can make some new shafts, thinking of making a few of various lengths and maybe even one with an ER11 or even ER8 on the end.