welllll...... Correct me if i'm wrong but couldn't you add gui to a script that targets the current weapons ironsight (sorta) and make the 1st person gun invisible to yourself.
Add gui to a script?
Target iron sights?
These two things are the things that i don't think are possible.
Add gui to script, because i don't even have a clue what you are talking about.
Target iron sights, because iron sights are just a part of the model.
I guess the best way to make the script detect a gun's iron sight is to make some sort of mountpoint or something similiar (like muzzlepoint or whatever) at the ironsight.
And that would mean you have to alter the model.
Another way is to manually set the eyeoffset at the right point for every gun that exists, but that is nearly impossible to do.
So you can make it for just SOME of the gun's, with only touching the script.