346 half-flanges on blind drivers

I guess I'm going to raise another "green boiler jacket" type issues. But after
reviewing some of the past posts concerning half flanges, it got me thinking.
Do I have anything in file other than book photos to confirm or deny the 'it
was done on the C&S'?
I seem to remember a long ago thread about this where I conceded that RWR
must have been mistaken.
However, after scanning some of the OP-DPL photos of the 346 at 7th St. after
repairs, but still in service pix. There were the half flanges.
Hope these attachments can be seen. OP took two pix of the engine at 7th St.
inbound track. Of the two pix, one shows the complete loco while the other was
after moving the engine a few feet, a portion of the driver area was enlarged &
lightened.

When looking thru Grandt's NGPictorial (C&S) book, it is difficult to see even
the half-flanges on the C&S power and then only under the best of conditions.
It is easy to see why this created so much discussion in the past.

Also, does anyone know of any practice on the Grande where they machined in
half-flanges on any of the slim gauge C class power? None that I know of.
The half-flanges to our street railway brothers are the minimum height for street
railway equipment accept of course a proper flange profile rather than squared off.

What interested my thinking was around 10 months after the 346 returned to
the Grande,they put the engine in July 1937 thru repairs that included a new
firebox. Perhaps the last firebox put in on a C-19? Did any repair records for
the 346 (donated from C&S 7th St files) that referenced the work done at the
New Joint Line Shops come to light at the museum? Or from Ala for that matter?

My thought is that with all the work the C&S put in on the wreck repairs, the Grande
must have thought the condition was good enough to AFE the money on a new firebox.
I don't it was just because of a new cab!

Consider this: If the accident hadn't happened and with the subsequent repair, the 346
might have gone the way of the 343, probably to never turn another mile in revenue
service on the home road.

As another issue, one might ask, when did the C&S start to apply the half-flanges
to it's own power? Some photos show in the tens to early teens. And I wonder why?
Was it partly done account of some of the 30degree curves and more miles of lighter
weight-per-yard rail on the lesser used branches etc?

Thoughts?

Chris