I know this was posted a while ago, but just managed to disassemble this hedge trimmer.
There two further screws hidden under the black blade cover.
Remove all of the screws in the black blade cover and rotate the blade section 90 degrees to allow the screw side of the black cover to pass the blade rotation button. You may just need to gently tease the housing apart. As it opens you will see the drive spindle and cog wheel and the green switch and trigger section will separate from the blade section. You will see the hidden screws.
Be careful to note the position of the triggers for reassembly. Also note the position of the collar surrounding the drive spindle, it has two flat sided.
Also be careful when removing the trigger switch as it is mounted on two plastic pillars which can be easily broken.
Hope this help.
Richard
April 2017