Calling US Steel Road Experts! Color of DM&IR logo?

Well there are two possible sources off the top of my head.  The museum in Duluth has an SD18 restored with the logo you are trying to reproduce.  And there is a DMIR historical society that would likely have the data you're looking for.

If all else fails I'd suggest contacting one or the other.

The DMIR Historical Society site has a page on logos with graphics which will not load on my phone.  I have to imagine somebody in that organisation has color specifics.

Thanks for the insight.  I registered to become a member of the DMIR Historical Society on their web page this morning and just need to hear back from the administrator for approval.  I was unaware of the restored SD18.  I will follow up in the morning.  

I can't begin to tell you how hard it is to track down some colors!  Had to order some replacement parts for my airbrush to make the samples for a few other colors I need