My late model angle eject with the stupid lawyer-proof crossbar safety is NOT drilled and tapped for a receiver sight.
The easy way to check is look on the left side of the receiver. If there are two screws, about a quarter inch below the top of thr receiver, and maybe seven-eigths of an in apart, then you won't have to drill and tap. No screws, time to visit your friendly local gunsmith.
Paul B.