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When Santa Fe added the second mainline between San Bernardino, CA and Belen, NM in the 20s, the railroad wanted to run everything right handed, westbounds on the north track and eastbounds on the south track. But the west side of Cajon Pass required that the new line be on the north side. To get things back to normal, the railroad added a flyover at Frost. Train 898 (Extra 3443 West) crosses over the eastbound main on November 3, 1977. The train has engines 3443, 3239, 3423, 3332, and 3364. Disk 50