How can I fix the rubber membrane?

It took me four days to figure out that you have a Mac Mini not a MacBook

Mac mini Take Apart General Information Thermal Pad The thermal pad is located on the bottom housing. A new thermal pad is included with the logic board and the bottom housing, and the pads can be ordered separately as a kit (part number 922-6749). Replace the pad when:

•the logic board or the bottom housing is replaced

•the pad is torn, withered, or damaged

Important: Never use thermal paste in place of the thermal pad. You must replace the thermal pad with a new identical pad. Procedure 1.Remove the original pad from the bottom housing or the logic board using a black stick or other nonconductive nylon tool. 2.Remove the protective backing on the new thermal pad.Note: Avoid unnecessary contact with either side of the thermal pad as dirt and body oils reduce the thermal pad's conductivity. 3.Place the new thermal pad on the bottom housing (as shown). Make sure the thermal pad has even contact with the bottom housing. There should be no air pockets.

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