Info wanted re: Skagit B-20 donkey

[Ray Dunakin]

Does anyone have any information on the Skagit B-20 Logging and Loading Donkey? I came across one during my recent Nevada/Mojave trip and have not been able to find out much about it online.

[Geoff Ringle]

Ray, is this it?
http://www.rootsofmotivepower.com/donkey-skagit-b-20f-yarder-20a186

[Ray Dunakin]

That's the same info I found. I was kind of hoping there might be more information about the differences between models, and the years they were built.