It does look like an RT910 or similar, for sure it is a Roadranger 10 speed, not a 13 speed.
The tag does not look like I would expect, perhaps it is from a rebuilder, and not the original tag.
A lot of Fuller/Eaton/Dana/Roadranger info can be found here:
http://www.roadranger.com/Roadranger/servicesalesliterature/index.htm

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-