While the First Help waits on track #1, Union Pacific's Salt Lake-Denver (MRONY) manifest rolls by on track #2, prepared to stop just east of the crossover at Castilla. After dispatcher #78 flags the UP 7700 by a red signal from main #1 to main #2, the helper will couple to the last car of the MRONY and prepare to shove the long manifest east to Soldier Summit.
