There is an April 1864 regimental return with the surname Soules or Saules, but no given him which lists this soldier in Company C, 33 Texas Cavalry and absent with out leave since April 29, 1864.

Please keep in mind that records are somewhat scarce, and also there are a number of soldiers with similar phonetically spelled names who might be the person whose records you are seeking.:
Sowell, J.M.
Sowell, P.
Solis, Juan
Solis, Eugenio
Solis, Seferino

All of this material comes from :
Publication Number:
M323
Publisher:
NARA
National Archives Catalog ID:
586957
National Archives Catalog Title:
Carded Records Showing Military Service of Soldiers Who Fought in Confederate Organizations , compiled 1903 - 1927, documenting the period 1861 - 1865
Record Group:
109
State:
Texas
Roll:
0164 Thirty-third Cavalry (Duff's Partisan Rangers, Fourteenth Battalion, Cavalry)