Where exactly was Whitebreast Junction?

A gentleman named Michael O'Brien posted this snapshot of the control tower at Whitebreast Junction yesterday to a Facebook group I'm fond of --- The Forgotten Iowa Historical Society. And I've been banging my head on the desk this morning while trying to figure out exactly where it was at. 

I know for sure that it was located along the main line of the C.B.&Q. line (now Burlington, Northern & Santa Fe) about three miles west of Chariton, somewhere near the top of the Whitebreast Hill grade. But I started out by confusing it with Indianola Junction, about a mile and a half west of Chariton, where --- commencing in February of 1879 --- the switch was located that allowed trains to move onto and off of the new Chariton, Des Moines & Southern tracks through Oakley, Lacona and Milo to Indianola.

Whitebreast Junction's purpose, presumably, was to monitor and control traffic on the Whitebreast Hill grade, descending to (or ascending from, depending upon which direction a train was going) Cleveland and Lucas in the creek valley below.

This steep grade had been an issue since the rail line first was built west from Chariton during 1867-68. An extra locomotive was needed to boost heavily loaded trains up it, braking on the descent was sometimes a problem, accidents were not uncommon and a staffed control station was needed to transfer trains onto and off of sidings so that collisions on the hill did not occur.

The C.B.&Q. line west of Chariton was single-track until 1899, when a second track was added; and even then, the Whitebreast Hill stretch of rail remained single-track for quite a few years because of the engineering challenges (and expense) involved in adding a second track on the grade.

And now I've exhausted the time available to fuss about this for today --- so locating Whitebreast Junction and its neighbor, Amity, will have to remain a work in progress.