Which coup d'état was the most difficult to execute?

Here are some successful coups:
1 Wihwado Retreat
2 First Strife of Princes
3 Gyeyu Jeongnan
4 Jungjong Restoration
5 Injo Restoration
6 May 16 Military Coup
7 December 12 Military Rebellion
Which of these do you think succeeded despite facing the highest level of difficulty?