Here I'll just copy/paste the post here:
Both full size and TKL logos are put on by sticky stuff in the back of the logos. They're not screwed on or punched on or anything. I took them out by carefully taking an exacto blade and gently pry up one side first, then just took my finger and lifted the rest up. The sticky stuff was still on the back, so I just swapped and pressed the logo back into the carved out hole.
Full size 104 case with logo pulled out. Also notice there are two little holes in that slot, which you can poke out the logo from the inside out if you took the case apart.
TKL case with logo pulled out. Notice the two holes to push out the logo is not present in the TKL case. Only way to take off the logo is use a sharp blade and carefully pry out the logo.
There are the two logo I'm about to swap. There's sticky stuff on the back, so that's how they stick to my fingers.
I replaced the gunmetal colored logo with a pure black colored logo onto this full size case.
http://geekhack.org/index.php?topic=25688.msg505965#msg505965