Now it appears I have found the first proof of GN units running in the 60's, pre-merger. Check out this photo from Karl Rethwisch:
GN Power on Burlington rails was actually quite common at various times. A good resource for this is the last chapter (“Great Northern – Tourists on Foreign Lines” of “Great Northern Color Pictorial – Volume 2 –“ authored by Joseph W. Shine and published by Four Ways West.
GN power shows up on the C&S, FtW&D, CB&Q, as early as 1958. Sometimes it was leased, sometimes it was pooled.
At one point in time, CB&Q E7’s handled the Empire Builder from Chicago all the way to Havre where they were swapped for F units out of the GN passenger pool for the trip to Seattle and back. On the return trip, the swap was reversed and the Q E’s handled the train all the way back to Chicago.
In return, GN F units on some Eastbound freights were not swapped out in St Paul but ran all the way to just outside of Chicago and return.
There were other arrangements in place in anticipation of the various merger dates. Some arrangements were discontinued as the merger was delayed again, some continued.
The pics in Shine V2 show GN power in various places on the Q system – worth a look for anyone interested in this topic.
Best regards,
Steve
Steve Haas
Snoqualmie, WA