Many Arkansans served in regiments organized in other states; men from other states served in Arkansas regiments; many (at least 2,000) served in both Confederate and Union regiments. Then there is the question of what does one mean by Confederate service? Does one include the State militia, State troops, local defense troops, home guard companies, quasi-official partisan ranger companies. Does one include Arkansans who served in the Confederate navy and marine corps?
A man could devote his entire life to researching this field of interest.
At any rate, give me some time and I'll pull together some numbers for you. As far as I know, I have the most comprehensive Arkansas Civil War soldier database around; at least, that's what I've been told. Even if that's true, I know that it is, and always will be, incomplete.