I found this great picture of the 3rd Tennessee battleflag on the Tennessee State Library and Archives website...complete with battle honors as you have described!! Way cool! Thought I would share it with you if you hadn't seen it already...which I doubt!
Too bad the 3rd went to Murfreesboro with Forrest for the Battle of Nashville...! I suppose I could make one for the 20th Tennessee that would look a lot like this one...just have to figure out the right battle honors. Any ideas?