I found Nicholas in the Worth County cemetery book buried in Poulan Cemetery. His marker reads, "N.M. Bowen Co. B, 11th GA Regt. C.S.A (Mar.18,1844 - Jul.17, 1925)",there are other Bowen's buried there as well. I can provide directions to the cemetery if you need them. Another one of my ancestor was from Worth County in the 14th Georgia and I've done extensive reseach documenting the grave locations of those soldiers. I could take a photo of Nicholas' grave the next time I'm down there if your interested. If you go to the GaGenWeb under Lee County military records I've compiled all the soldier pension records for Co.B Lumpkin, Nicholas, and William's records are listed there. Let me know if you have any trouble finding them. Do you have a direct email I can send the unit history information to?
Here's the muster records for the Bowen's in Co. B:
Bowen, Benjamin C. Private March 4, 1862. Surrendered, Appomattox, VA April 9, 1865.
Bowen, Lumpkin Private February 22, 1862. Wounded at 2nd Manassas, VA August 30, 1862. Appointed 1st Sergeant July 2, 1863. Surrendered, Appomattox, VA April 9, 1865.
Bowen, Nicholas M. Private May 6, 1862. Surrendered, Appomattox, VA April 9, 1865.
Bowen, William S. Private May 6, 1862. Surrendered, Appomattox, VA April 9, 1865.
(Born in Baker County, GA April 21, 1838.)