[sonny]

Subject says it all.......I got a colt xse and I want to put in a beavertail ,slide release and safety etc.

[stans]

Slide stops usually do just drop in, although the portion that contacts the magazine follower may need to be adjusted so that the nose of a live round will not prematurely activate the stop. Thumb safeties almost always require fitting to make them function properly. I am not a fan of drop in beavertail safeties, they do not seem as comfortable as the ones that require machining of the frame.

[1911Tuner]

Most drop in and work often enough to be called drop-in...but
it would be wise to approach the job with the attitude that
there is no such thing as a drop-in part. That they will work
isn't a guarantee that they will work properly.

Slide stops, recoil systems, springs, pins, firing pins, firing pin stops, ejectors, mainspring housings and barrel bushings work on a drop-in basis without fitting or very much fitting often enough. Not always, but very often. Extractors usually
require no more than a little adjustment.

NEVER assume that a trigger group or any part of the
group will drop in and work properly. I've seen them
do it, but it's a dangerous crapshoot. Advertising a
"Drop-In Trigger Job" is bordering on criminal. Too many
variables that are beyond the control of the parts maker
to trust it.

Cheers!
Tuner