“I believe the calvary opposition during the battle was along the river and up a small hill. Maybe not suitable for positioning those guns.” [morphing libertarian, post 164]
Small hills are no part of the terrain there.
The land on east side of the river rises in bluffs that top out 50 to 150 ft above the floodplain; a great number of gullies and washes are cut back into the upland territory from the river. Pretty much infeasible to get any artillery train to the area from the southeast, or to move emplacements about the area. Gatling guns were no smaller nor lighter.
Plus, hardly anyone had worked out just how to use what few rapid fire arms existed in 1876. Repeaters were newfangled and unproven: Plevna was still more than a year in the future.
I guess that was what I was referring to as hills. i was at the site and remember it was not entirely level. We started buy the center and went out and down a decline where some markers indicated where items were found. Maybe they would have pout the guns up on the bluff and waited there?