Here's some information on your gggf's regiments that might be of interest.

The 3d SC Reserve Infantry was organized under authority of a resolution of the SC Executive Council, dated 24 April 1862, ordering the formation of a reserve force of male citizens between the ages of 35 and 50 years. The regiment performed 90 days Confederate service at Camp Goldsmith, near Pocotaligo, SC, from 13 November 1862 to 11 February 1863. Co. C was from Greenville District.

The 1st SC Infantry, State Troops, was organized on 23 July 1863, in response to a request from the Confederate Government for 5,000 troops for local defense and special service. It entered state service on 12 September 1863, and after assembly at Charleston, SC, was transferred to Confederate service. The regiment served at Charleston until discharged on 1 February 1864. Co. G was also from Greenville District.

Hope this helps.