I understand that during the civil war ,there were many,many flags of the Great South Armies

I'm looking to see if the 23rd Mississippi Inf. had a Regimental flag. My Ancestors fought with the 23rd E Co.

Also My G G grandfather was with General N.B. Forrest Co. E. Nixon's 22nd Cav. would they have had there own flag.
or under Forrest were they all under one flag ,if so what would it have been, where would I look for such info.?

the last one is was with the 55th Alabama Inf.

thank you for what you do.