Adding to what George Martin has posted, here is information from his compiled service records as found at Fold3 and from Adjutant General's Special Orders from NARA:

Guilford L Dudley 2nd Lt Co E 1st North Carolina promoted to Captain & AQM Nov 1, 1861 [other cards says Nov 6 and Nov 9]

2/24/62 Richmond, A&IGO Special Orders No. 44 Par 22-The following officers, Captains in the QM Dept, having failed to give bond will have their names stricken from the rolls & from this day will cease to be officers in the C S Army
G L Dudley 1st NC Volunteers

March 17, 1862 Restored

G L Dudley Captain appears on a report of quartermasters & assistant quartermasters on duty with the Army of Northern Virginia. Report dated Nov 13, 1862. 1st NC Bonded

G L Dudley, Capt & AQM, 1st NC, Stewarts Brigade, Johnson’s Division, 2nd Corps, A.N. Va Nov 13,1863
See list No 1 Quartermasters & Commissaries A.N. Va filed with Dept returns

Guilford L Dudley AQM 1st North Carolina
Appears on field & staff muster roll for Feb 29-Aug 31, 1864
Remarks-Transferred
Relieved from duty with this Regt by order of Sec of War
Assigned to duty with Maj Cameron, QM Wilmington, NC

8/11/64 Richmond, A&IGO Special Orders No. 189 Par 35- Relieved from duty with this Regt by order of Sec of War and is assigned to duty with Maj Cameron, QM Wilmington, NC

Guilford L Dudley AQM 1st North Carolina
Appears on an inspection report of Rodes’ Div, 2nd [Early’s] Corps, Army of the Valley Dist
Bunker Hill, Va August 20, 1864
Absent sick
Cox’s Brigade

Dec 21, 1864 Signs invoices in Wilmington, NC

Guilford L Dudley AQM 1st North Carolina
Appears on a roster of the 1st North Carolina dated Feb 1865
Remarks-Office abolished by act of Congress

March 23, 1865 Richmond, A&IGO Special Orders No. 68 Par 24-Capt G L Dudley AQM is assigned to duty in connection with railroad transportation at Raleigh, North Carolina and will report to Maj H R Hooper QM. Captain Dudley will also render such assistance to Captain J M Robertson Military Superintendent at Raleigh, NC as he may require

May 2, 1865 Paroled at Greensboro, NC