how about- our general was drunk and we still whooped you rebs?
It's a little less objectionable. But why do it at all. Why go out of your way to offend people.
About ten years ago, I took a tour of the Gettysburg battlefields with a guy who was a near expert.
Based on this experience, I started to read books on the war. (More American books have been written about the Civil War than any other topic.) When I finished reading a number of books, I had only one overriding emotion; sadness.
Death, disease,suffering, fear, deprivation, piles of amputated limbs outside of surgical tents, waves of grapeshot tearing through rows of soldiers, etc.
It was a huge American tragedy. Princeton's James McPherson suggested that it was unnecessary as the economic conditions that brought it on were going to resolve themselves anyway. He also said that soldiers on either side would have never agreed that the war had anything to do with ending slavery.
The North won because of what Lincoln called "The Arithmetic" far greater resources and many more people. The South depended upon quality of the soldiers and the brilliance of their generals and almost pulled it off.
The drunk you are talking about replaced a series of Generals who refused to fight Lee because they believed they would get their asses kicked.
Southerners, in my experience are generally much more aware of Civil War history. Most of it was fought in the South and the area has endured the after effects for many decades. Northerners usually have Cliff Notes-level knowledge (e.g. Sherman marched through Georgia. )
You are a creative guy. There's got to be something else in your arsenal of wit beside Civil War "jokes".