Another Y-6b detail question

[NW Modeling List]

Hi,

There is a box underneth the enginers side running board, above the front
engine, on some N&W Y-6b's. I assume it is a train control box, but don't
know why I see it on some pictures of the engine, but not others. Can
someone tell me what determines when/why an engine was so equipped.

If I'm right that it's a Train Control Box, it sure doen't look like the
common Calscale HO brass casting. Custom Finishing has a couple that look
closer. Any comments on a good brass casting to represent that part on a HO
model of the Y-6b ?

I'm making pretty good progress on my PFM Y-6b rebuild project. When it is
done I'll post a link to pictures so you can count the rivets and tell me
where I screwed up :)

Regards,
Dave Ayers
daveayers.com/Modeling/