How do I remove the rear, ramp sight (Marbles) on my Pre 64 Win. Model 94 SRC?

I want to remove the Marbles style ramp, rear sight on my old Model 94. The gun was mfg. in 1924 as verified by my serial number. I am not sure how to proceed with removal of the rear sight. This style of sight is a buckhorn type. It has one, small set screw to allow adjustment of the tiny elevation piece inside the buckhorn section. I can find no other screws holding this sight on. Is it dove tailed, press fitted? Not sure how this is attached to the top of the barrel. Please help. Thanks. Doug