hmm.. how can i tell you that in English..
1.Take a Photo from the every Step you made..
2.Wrote it on a Letter what you do and how much screws you have..
3.Put this things in a bag...
At the End you have ~42 Bags and ~ 80 Photos (to much to upload here)..
Try it... And if you do it, you can clean the Fans from the Dust and put new Paste on the CPU and GPU..
If you wanna need help at this, i can help you..
An example:
Wrote on a Letter:
Step 42
1.Unplug the Subwoofer with 4 Screws..
2.Than Make a Photo

3.Than put all this Things in a bag an wrote Step 42 on it..
Than you can see what you have do and where it come from..