Drop bottom gon question

All:
I just finished my PBL drop-bottom gon model and got it painted. While pondering the photos in the Grandt book for lettering, I noted the following interesting observation.
Photos in the book either show no logo, the Royal Gorge/Moffat Tunnel logo, or the speed logo. There are no photos with the earlier Royal Gorge logo, which leads me to wonder if these cars were among the last to be rebuilt and this occured in the few short years when the RG/MT logo was in use?
Anyone seen a photo of these cars with a RG logo? Along with the tank cars, they are unique to the narrow gauge with so many steel parts. If you have not seen the PBL model, it really does the prototype justice. Even down to the cotter pins on the end of the door levers!
Keith