In terms of exterior lighting, does anyone know what sort of lighting F7B locomotives had?

I have a A-B-B-B-A set of F7 locomotives, in Great Northern colors. I got them used, and they had seen better days, so I have had to clean them up and refurbish them extensively. As I do so, I am adding DCC and appropriate lighting, but I am not sure what would be appropriate on a B of the F7 era. There do not appear to be any molds or detail parts that look like headlights or marker lights.

I want to change the smoke volume in a MTH Challenger Steam locomotive.
I already know that you can modify the smoke volume toggling Function 18, and that It can be varied in three levels: low, medium and high.
However It is not enough for me. I consider that the Locomotive should throw more smoke, I would like that!
I am completly sure that there is a CV, or two or three of them, that can be modified to achieve the effect I want, but I have not been able to get this información anywhere.
Wich are the CV variables that control the smoke in a MTH Steam Locomotive?

I am working on a SD 75 by Athearn. It is a undecorated model. I need to know how to take the trucks apart for paint. I have them off, but can not figure out how to remove the side trucks. Can someone please point me to some directions or tell me how?

Thanks Alan

I have a new Bachmann Bethlehem Steel 100 Ton 3-Bay Hopper in D&RGW paint, and I want to convert it to NW paint and try my hand at weathering.  So far, I've tried using 91% Alcohol on a cotton swab and though tedious, it seems to be working.  

But I wonder if there's another, quicker method for removing the white lettering from the black base paint?  I'm open to tips, tricks, or suggestions.