I like Uberti Special Sporting Rifle so much that I recently got a very similar Uberti 1866 Yellowboy carbine, also in 45 Colt, to go with it.
It turns out that with it's early model flip up rear sight, after I filed down the front sight (shooting really low) I was able to dial it in with my lower power std pressure loads I use in both my rifle and pistol so that:
* With the rear sight down, I'm on at 100yds
* With it up using the notch at the bottom of the aperture, I'm on at 200yds
* With it up using the center of the aperture, I'm on at 300yds
* With it up using the notch at the top of the sight I'm on at 400yds.
So, I don't need a tang sight for it (other than the help the small aperture close to my eye gives me by increasing the depth of field). Further, while I haven't got around to chrono'ng my loads yet, it seems to me that I get a bit more velocity in the shorter barrel of the carbine so the round has a bit better 'legs' out at longer range. That isn't really important as with my eyes, anything over 200yds is a stretch anyway and the tang with a target aperture really helps me see the front sight and target much more clearly.