Here are some local ones that can be found.

Fort Davidson
Ironton Camp Sites
Fort Benton, Patterson Mo
Stoney Battery, Southern Iron County
Centerville above the courthouse, where an entire unit was captured.
Pulliam (the site of the alleged massacre by Wilson).
Doniphan, MO.

Also probably

Ellington, MO (Deer Run Forest)
Van Buren, MO

You could probably read the book "Marching with the First Nebraska" and although it doesn't talk about the 3rd MSM, you could follow some of their marches and those would more or less match up with later marches by the 3rd.

Walt Busch