The UP Gila Sub is the ex-Southern Pacific Sunset Route that runs 255 miles from Yuma, AZ, to Tuscon, AZ. When I found out of a possible signal replacements coming this summer 2017, I made plans to go get the remaining SP signals. Plus UP has been putting double track in along this route, and those plans also have replaced alot of the old SP signals too. Back in 2017 roughly only 85 miles of original SP trackage is left with old signals along the Gila. Early morning finds this eastbound auto train from Mira Loma, CA, bound for Nogales, AZ, (Mexico Border) working hard up the 1% grade passing East Shawmut. Ex-SP Searchlight signals are still used in this area between Shawmut and Piedra.