Western Pacific's "covered wagon" (an affectionate nickname for these carbody type locomotives) fleet consisted of an equal number of "A" cab control units and "B" booster units. As the units grew old and were traded in on newer, higher horsepower units, the "B" units were first to go because of the versatility of the cab equipped "A" unit. By the time the Feather River Rail Society established its Portola Railroad Museum all of the WP "B" units were gone. Still, a "B" unit was desired to represent this type of locomotive in our collection.
In the late 1980's, the Canadian National Railway still had some "B" units that they had recently sold for scrap. Arrangements were made to purchase one of the units in operating condition and restore it to represent a WP "B" unit. This unit was repainted in WP's classic orange and silver "Zephyr" paint scheme and given a fictitious WP number.