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Is accessing the CPU the same way in the Late 2013 MacBook Pro 15”, like it is in Mid 2015 MacBook Pro 15"? Solved overheating problem on my MacBook Pro 15" Mid 2015 by replacing the thermal paste
Its basically the same, I do recommend taking the logic board fully out as the mounts are only glued to the PCB! So when you press on the board the adhesive will often fail as you press down as they is nothing below it to hold the pressure. I use a block of hard wood which I routed out with a slot so the small SMT devices are not crushed supporting the PCB directly where the mounts are. Here’s the needed guide MacBook Pro 15" Retina Display Late 2013 Logic Board Replacement. Apple uses a sealer on the screws so you’ll want to either use some solvent or heat the screw to release the screw. If you do pull a mount off you’ll want to use some Cyanoacrylate glue (Crazy glue) to remount it. Make sure you don’t touch the surface or try to clean it and take note of its position so you place it back down exactly in the same orientation.