Son-In-Law kind of panicked, The (Bubba) gunsmith DID hack of the front sight just above the gas tube. Now a new sight of his choice. I told him to take a look at the tip off sights if the standard sight bothers his field of vision with a scope.
If the gun doesn't have a fixed rear sight and/or if the irons are strictly to be backups to an optic, he might look into a folding front sight. Out of the way most of the time but can be instantly raised (usually spring loaded) for use if needed.
It's a Colt LE6920 with the removable carrying handle and military type adjustable rear sight. The tip off or fold down sight would both work. He should have left the thing alone and talked to me first. He's a pretty good Son-In-Law otherwise, but he is an ex-Marine and I take that into consideration. Carries a Glock 21, so sometimes he listens.