Figure 1 shows the package of the Williams SKS front and rear sights.
The rear sight of the SKS is really easy to remove.
There are no pins to drive out.
At the front of the sight leaf there are two trunnions that the sight pivots on and is also held in the sight base by.
There is a flat spring that places upwards pressure on the rear sight leaf and keeps the trunnions held in a slot at the front of the sight base.
If you press down on the flat spring you will be able to pull the sight leaf to the rear and out (as shown in figure 3).
Figure 4 shows a trick to insert the supplied pin that comes with the Williams rear sight. I found it difficult to try and keep pressure held on the rear sight's flat spring and drive the pin in at the same time.
This is really a job for three hands!
With a plastic quick clamp and a punch (or flat narrow object), I was able to keep the spring held down with constant pressure applied. This left my hands free to handle driving in the pin.
Next, drive the pin into the holes on the rear sight base.
Note: Be careful to make sure the pin is driven in far (flush) enough to allow the gas release lever to move freely. Otherwise it will stop the lever from moving full arc, when you are trying to remove the gas tube for cleaning.
Installing the new aperture sight is also very easy. Just press down on the flat spring and slide the sight under the installed pin.
The sight is held in place between the pin and the spring. It is very secure and stable.
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