First of all, turn off your laptop Lenovo G570 / G575 / Z570, disconnect the the AC adapter and remove the lenovo g570 battery.
1. Turn over your laptop and loose the five screws securing the memory / HDD bay compartment cover, but don't remove the screws.
2. Remove the memory / HDD bay compartment cover, now, you can access the fan assembly.
3. Unscrew the three screws and unplug the fan cable as shown, now, you can remove the fan. You can find the new Lenovo G570 / G575 / Z570 fan here.
4. If you want to replace the Lenovo G570 / G575 / Z570 keyboard, please remove these three screws. Next to each of the screws is a small sketch of a keyboard etched into the plastic casing to help guide you.
5. Now, open you laptop, push back the 5 tabs which are located above the 'F1', 'F7', 'F11', 'INSERT' and
'PAGE UP' keys. Then, lift up on the keyboard.
6. Lift up the keybouard a little from the top edge of the keyboard. Then unlock the keyboard cable from the motherboard. To do this, simply lift the lockdown clip approximately 90 degrees.
7. Now, you can remove the keyboard. You can get a new Lenovo G570 / G575 / Z570 keyboard here.
Reverse the procedure to install your new keyboard.