Has it ever been done before? I'm curious. And if it hasn't, how would you attempt it?

Yeah, that's pretty much all I want to know.

3069507
If it were me, I would leave it unsaid that he was blind until the end and leave it as a twist. Like, when he describes things, he always uses senses other than visual cues to describe it. Subtle foreshadowing.

3070013
Can't do that if it's first person. You have to go by the character's senses.

Exactly.

3069507
I don't believe I've ever encountered a book or story where the character is blind. It's an interesting twist if you want to pull it off that way, but I can also see it being a great plot device.

I'm not sure how much this would help, but writing in first person would leave the character as an unreliable narrator. Going by that, they could make up colors and other visual cues, with subtle hints at the fact that they aren't sure it's really what they say.
-SoI

Has it ever been done before?

Yes. Blind was started by DarqFox months ago, but never finished. It is still being worked on though.