Hi Ross,
Is the N.B. Forrest #3 a SCV camp? Since the 24th Ark was part of the Army of Tennessee most likely the flag design you asked for might be the Hardee/Cleburne battle flag. Go to this link (cut & paste for the exact page) for the general pattern:
http://www.confederate-flags.org/confederate%20army%20of%20tennessee.html
Maybe our professional flag historians have additional information on this flag in their files. Hope this helps.