Under the Monitor and then unscrew th Keyboard fixing screws. Remove the Ribbon Cable from the Keyboard to the M'Board and refit the new Keyboard in the reverse Order.
However with any form of Liquid Penetration the entire NB should be stripped and cleaned. Depending on how much Liquid has entered the unit it may be worthwhile just pulling the HDD and fitting it to a USB Caddy and recovering what is possible in the way of Data.
If there is any sign of Liquid Penetration on or near the HDD you should also scrap that as well.
If the Liquid had sugar in it like Soda or Coffee the Chemicals will attack not only the Circuit Board but the components soldered to it and destroy everything. Applying Power while in this condition will only hasten the destruction of the unit.
If you want to buy a New Keyboard you can order one here
http://tinyurl.com/a3ede
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