BNSF SD75M's

Hi from the UK, been to So Cal several times recently to photograph BNSF or ex SF SD75M’s and had no luck. Been on Cajon and Tehachapi, been past Barstow and Commerce and not one to be seen. I plan to come to the states again in the fall to seem them, anyone able to help so I can plan my trip.
Thanks

Well there aren’t that many, are there? I’ve seen one up here in the Columbia Gorge, and the big freight engines tend to get spread around all over, so I would just say keep trying… unless a BNSF fan can tell you where you might find one easier.