i added more pics to my "reference folder" on my computer. I may do this paint scheme, its only on 2 loco's.
Are decals available for those?
You can use sheet styrene behind the housing. If you want to light then later, cut out some clear plastic (like the ones that come in clamshell packaging for electronics) and use that.
Then, I'd decal over the sheet styrene/plastic (Shellscale numberboard decals are nice, especially if you want a white board with a black gasket)
Let me check my parts pile and I will see what I have that might work for you.
With the fiber optic side lighting, instead of forming the cables into T shapes why not just have a separate cable for each side that runs to the same LED? Six cables total, but only three LEDs, one for each colour.
Well this is what I have and I am using your SD90 loco for reference.
holy crap, i think that would work dam near perfectly.