Since it doesn't letter in this configuration I wouldn't worry about much on this gun. However, regardless of how it letters, it's a pretty decent looking 1885 and I personally would leave it as it is, and just reline it to .32-20 again.
I would return the set trigger system if you can find or make parts, but I wouldn't worry if they weren't factory sinc ethey're internal and not lettered too.
Looks like it had some sort of tang sight at one time judging from that extra long tang screw too. Might not hurt to put a correct Lyman or Marbles on it if you can find one.