Yes, that is what I was imagining Mitch! A western GG1; cool!!
The basic idea is that UP decided to electrify between Chicago and Los Angeles, following the Milwaukee Road's example in the Cascades. UP's reasoning was that the higher initial infrastructure costs would pay for themselves in terms of schedule improvements, reduced fuel requirements and so on in comparison with heavy steam locomotives. Since the Pennsy GG-1 had a proven track record in high-speed electrification service, UP licenced the design from PRR.
This also inspired the PRR to complete the Harrisburg-Chicago electrification project, allowing an all-electric ride from coast to coast while simultaneously slashing both freight and passenger schedules.
The project wound up working well, and is maintained to this day with New York-Los Angeles Acela sleeper service being offered by Amtrak and with UP and NS using Siemens freight engines between the coasts... ;-)
Weep not for the Big Boys and their like, however, as they were used on on the vast majority of UP's track (not electrified owing to cost). ;-)
On the West Coast, the Southern Pacific expanded their heavy electric lines from the San Francisco area up and down the Coast, resulting in bloody nosed and Daylight EP-4s sourced from the New Haven operating between San Diego and Seattle!
Mitch