Penny, I would agree the D is an index letter.The #1 the part you can't read (XXX)is most likely Dept.of the Cumberland.The fact he was sent to Ft. Monroe for exchange would make me think he was exchanged and would have been returned to his regt.Many individual records are lost especially late in the war. I'm not sure as to Morgans records.Morgans CAV. was to my knowledge formed from KY.There might of been a ALA. group in the regt.as consolidations occured as time went on.I am not sure. I would believe these are two seperate men.Just a guess but, the #2 seems more plausable as your kin from your own words. Sometimes pieces of a puzzle are missing.The picture can still be determined.