Congrats! Let me try to help. For general cleanup, you don't need to remove part #4, just #2 occasionally, and the needle. After I spray, I flush the airbrush with Windex (I only shoot acrylics), then flush with water so as not to leave ammonia in contact with the metal.
Then I remove the needle. Do this by removing the handle #16, then loosen nut # 15 a few turns, and gently slide the needle out. Wipe it down with windex or alcohol, and gently (notice I use that word alot when talking about the needle!) slide it back into place until the neeedle tip is seated, and protrudes a little from the nozzle #3.
The screw labeled #14, valve screw should be screwed all the way in. You can loosen it a bit, and this will make the trigger a bit easier to move, but not too far.
Lastly, when you need to clean the nozzle an air body, which I don't do very often, the wrench included WILL turn it, but it takes a bit of torque with a new airbrush. Apply pressure gradually, but firmly, until it starts to move.
Hope this helps, and good luck! Ask away if you have more questions.
Chris
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