I've been away from my notes for a few days and won't have access to them until the middle of next week so take this bit of info w/ a grain of salt... in short my memory may be all wet.
I'm pretty certain that I have seen an order of battle relating to the chasing around done by AJ Smith's foot
cav in late 64 early 65. IIRC there were several "Trans-Missississippi Battalions" in the
CS order of battle. As I understand it these were essentially ad hoc units thrown together from remnants of units, independent companies & conscripts. Being short lived and improvised units I would expect they might be rather hard to find info on.
When I get back home I'll see what I can find. NBForrest if you would be kind enough to PM w/ particulars it will act as a reminder and I'll see if I can dig anything up.