Attached is some information that I took from old maps a number of years ago. I found 4 references to boundaries between Lines East and Lines West.
At Pacific Jct., the boundary was shown on the line to Plattsmouth, west of the wye, at MP 475.482 Lines East = MP 0.337 Lines West.
At Omaha, the boundary was shown at the centerline of the old puzzle switches at the east end of the Omaha Depot. On the Eastward Main the equation was MP 496.20 Lines East = MP 16.576 Lines West. On the Westward Main the equation was MP 496.21 Lines East = MP 16.582 Lines West.
At Payne, the main to Lancaster began at MP -(MINUS) 0.07, and the boundary between Lines East and Lines West was at Payne depot at MP 0.00.
At Napier, the boundary was shown at MP 0.078 on the Napier to Table Rock Main.
At Atchison, no boundary was shown on the Atchison to Rulo Main. After this line was removed in 1933, the end of the track was at MP 0.79 north of Atchison, and all of the track at Atchison was on Lines East. Before the abandonment, it is conceivable that all of the CB&Q track in Atchison was on Lines West.
In 1968, the line between St. Joseph and Pacific Jct. was transferred from the Ottumwa (St. Joseph Lines) Division to the Lincoln Division. This should have meant that a new boundary was established somewhere in St. Joseph and the boundaries at Napier and Payne removed. I have an old map that shows a boundary equation at MP 64.62 north of Francis St., with the words Begin and End shown but the rest of the information is cut off from the copy, so I can't verify that it is a Lines East/West boundary.
Glen Haug