In addition to this mod, I have done a repaste with Thermal Grizzly Kryonaut and the results were very satisfying. Idle temperatures were around 60 something °C before, now around 40°C in combination with the thermal pads. Definitely choose quality pads, mine were EC360 Gold with 14,5 Mw/K 1mm thickness. Works perfect although the bottom can get very very warm. Having a Laptop-stand aids in thermal dissipation from below and helps keeping the temperature down. To answer the question of Andres Urena: No the result is not the same when comoparing the laptop on a stand with an additional fan and the naked thing lying on the desk. The bottom now functions as a huge heatspreader, so the effect will be greater with additional airflow from below :)

Very good, thank you. I changed the thermal paste on my 2018 Model with i7 CPU. I took the Thermal Grizzly Kryonaut and the results are very satisfying. Idle around 60 something °C before, now around 40ish °C.

Good point! I would suggest to use pure isopropyl alcohol and not something below 99%. The residual water might be not much but still there is a slight chance of it getting somewhere inside. Also the 99% pure alcohol evaporates much faster and leaves no traces. Apple batteries are also glued in with adhesive. What apple does right are the pull-strings to remove the sticky tape between chassis and battery.