This short video explains the history leading up to and the specifications of the two locomotives in EMD's 75 series: the SD75M and the SD75I.
Sources
https://en.wikipedia.org/wiki/EMD_SD7...
https://en.wikipedia.org/wiki/EMD_SD7...
https://www.american-rails.com/946503...
Yes, I used Wikipedia - sue me
Brookings Rail Watch
The official Brookings Rail Watch webpage:
http://trains.kf0cci.net
Pictures, Logs, and more