You may long ago have accumulated all of this info, but I am working on other men from MO and AR who were in several units who would up in Jacksonport and/or Camp Morton. I am am happy to identify as many of them as I can, in order to see if their histories hold some clues to break down some of my brick walls.

There were two men who served in the 7th Arkansas Confederate Infantry who might be related to your Milas Pinkney Presley...thanks to couchgenweb at
http://www.couchgenweb.com/civilwar/shaversa.htm for the roster.

PRESSLEY, DAVID
PRESSLEY, F. M.

There is a good concise narrative at this site: http://7tharkansas.campeastjack.com/7thhis.html
(Thank you very much to Pvt. Chase Clements, Jr., webmaster for the 7th Ar/5th KS "T" site.)

There is a large and well-documented family tree (with sources and photos) on ancestry.com under the name "Jimmie Neal Thompson Family Tree," author avatar "karmablue". Your Milas P. Presley was still alive as of 1920 (is on the census in Vance, Union Co, NC), but died on 21 Apr 1941 in Thayer, MO. There is a photo of his headstone in Jeff City.

U.S. Veterans Gravesites, ca.1775-2006
Name: Milas Pinckney Presley
Service Info.: CORP CONFEDERATE STATES ARMY
Birth Date: 3 Feb 1837
Death Date: 21 Apr 1920
Cemetery: Shiloh Cemetery
Cemetery Address: (Grand Gulf) Oregon County,MO Jefferson City, MO 65110