In this post I explain how to disassemble Asus K-series notebook and get access to main internal parts.
As an example I took a Asus K50IJ model. I believe disassembly steps will be same or very similar for all models in Asus K line.
Let me know if this guide works for you. Please mention the model number in comments below.
Make sure the computer is turned off before you start taking it apart.