That's true about the captured uniforms.
We've had a few threads about that topic, here are two of my favorites :
Here is a yankee greatcoat that is in the Alabama archives that has a great story behind it. I would say that with it being winter and the fact that Forrest Cavalry Corps had just captured a bunch of yankees, I guess Forrest ordered this for the obvious reason. Cavalry greatcoat worn by Pvt W...
civilwartalk.com
Cavalryman Bedford Forrest outfitted his command several times at the expense of the Federal government. “Every man had a complete Yankee Suit consisting of hats, coats, pants, jackets, and boots,” a Mississippian recollected. This posed an inherent problem which in 1864 caused Forrest to...
civilwartalk.com
Forrest was adamant that his troops dye the "confiscated" clothing so as not to be accused of impersonating the enemy.
I think he even gave his men a time limit to make it happen. From what I recall, I think Forrest wanted the captured uniforms
to be dyed brown. But in one of the above threads,
@John Winn pointed out his wife said that changing the color from dark blue to brown would have been difficult. So most of the uniforms probably did
end up a blackish color.
Regarding Forrest, I doubt he had to use captured Union clothing.