I did a RAM upgrade on a Mac Mini Late 2018. Take it slow and meticulously and make sure you follow the instructions. When you re-assemble the Mac, from the very first step when you insert the RAM and especially when you reconnect the cables make sure things are seated correctly and firm. I did not connect the fan perfectly and was greated with a very funny sound. It is very easy provided you have the correct screwdriver and good tweezers.