The only scary moment was removing fan from Vent. The two vertical 7.2 mm Torx T6 screws at the top of the fan are easy to remove, in fact almost all of the screws for me were easy to remove because I was careful to get a good lock fit on top of the screws and slowly, while pressing downward just enough to get traction and the screw would loosen. The angular 7.2 mm screws attached to the fan vent with grommets is hard to get a direct angle with original orientation, to get the best lock and traction and use more force as they are very tight. Started to use too much pressure when it wouldn’t move and without direct even tension, I slipped a few times and that always leads to stripping the screw head and your screw driver. Carefully see how they turned the case around, so you can get a better straight angle and once the top screws are off you can gently shift the fan around to loosen the screw grips with the rubber grommets and carefully unscrew .

This use to happen to me when upgrading 2012 mac mini’s. Have to use a spludger or something to hold connector down while you pull it upwards, flipping lightly on back of cable. it clips in, so don’t try to”plug” or insert.