screw locations likely in the battery compartment and around the dvd drive. Sometimes there is one in the HD compartment by my experience.. I would think removing the keyboard is the ticket if there is not a cover to access the memoyr on the bottom..
yes just remove six screw marked by blue dot as in the pic, however, you have to remove the battery and there are three small squares (clips) which need to be release before the whole plastic cover can be removed. I successfully did that this morning to clear the collected dust around the ventilation. Hopefully it wont over heat again