UP PROTOTYPE Paint Scheme used on Switch Engines - Diesels

Ray of sunshine posted:

I seam to recall some time back seeing a UP switch engine painted in all silver with either red, yellow or blacking lettering. I think it was an S2 or similar switcher. 

I've since done a search and can not find any such engine. Does any know if the UP had an all silver switch engine and where I might find photos of it?

Thanks,

Ray

The Union Pacific Historical Society shoes have all the answers on the website. Also, try Utahrails website.

UtahRails website has a pretty comprehensive page on when and what color.

http://utahrails.net/up/up-diesel-paint-index.php

Rusty