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To get the hammer mechanism out you will first need to remove the trigger bar which is held in place by the rear body pin which is retained by a C clip.
Pull out the C clip and then tap the pin through.
Remove the trigger spring.
Remove the trigger bar retaining block.
Squeeze the trigger and trigger bar together and lift the trigger and trigger bar up and out.
Next comes the hammer mechanism itself.
You need to remove the two forward push pins, one of which is indicated in the pictures below.
They are retained by two of KSC's lovely 0.89mm allen grub screws.
Remove them and then pull out the pins, they are a tight fit so be patient and don't smash up the gun.
Once they are out the Hammer assembly will come right out. It is another tight fit, be patient.
Look for these screws, they remove the recoil buffer.
Then you undo these two (one on each side) that hold the mechanism together.
Once they are out you can gently prise the mechanism open and remove the hammer and valve knocker assemblies.
Hammer assembly is just three parts, easy.
The valve knocker assembly is a little more complex, 7 components (one of which is a sub-assembly with 4 components that you shouldn't need to dismantle unless a part of it is broken) all built around a single push-pin.
Make sure you know how the parts fit together before you split them up by tapping the pin out.
Exploded shot of valve knocker assembly.
Last you remove the sear, to do so you remove the sear spring.
Then the tiny C clip - be careful not to loose it