The sight bases seem to be soldered on. I have removed the rear sight ladder assembly and the front sight blade and hood.
Front sight; tap the hood off, tapping toward the muzzle. Best to use a small block of wood and light hammer. The sight blade is sharp and will draw blood.
This will expose the sight blade and the adjustment/retaining screw. Loosen the screw and slide the blade forward and out. The screw is small and somewhat fragile. Be careful not to over tighten if you decide to reinstall.
Rear sight; The rear sight ladder is held in place with a leaf spring under the ladder. With the elevator in the lowest position, push down on the forward portion of the ladder and slide rearward. You may use your finger, but I use a quarter inch dowel or an unsharpened pencil. The leaf spring is not attached and may fall loose when slid out. This spring fits into a depression on the underside of the ladder.
Hope this helps.
Dave