Thanks for posting the pic of the Standard Oil Co. car.
When I scraped that car for a possible repaint, I was looking for a Gramps Tag or something else, like I had found on the Tank Car in Central City.
Instead, I found that Standard Oil Company lettering on the side of that car, I just painted over what was there.
The interesting thing about that car is that it had a stepped bolster and was used in broad gauge service as well.
I appreciate the pic because my shot of it, after I scraped and painted the tank in 1976 or 77, got lost.
Yes, it is a prototype lettering scheme, just not one used on the 3' gauge.
Rick