Some may drop-in, some may need to be fitted.
And most of time, you won't know until you have the new safety in your hand.
Are you real familiar with the 1911 and the thumb safety?
We have no knowledge of skill level.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Life Member NRA
Life Member NAHC
Former President of the ECPT (Eifel Combat Pistol Team)