This cache is hidden near the former Kinghorn Subdivision, which was abandoned in 2005 and the rail removal started in 2009.
Check out the locos. The photos have some minor edits to keep you on the right track with minimal math involed.
Cache is located at N48 v.x W88 y.z
Loco a, reverse first two digits = v
Loco b - Loco c = x
Loco d + Loco e = y
Loco f + Loco g = z