Well, My most recent 1911 - actually a Colt Officers ACP (circa 1985) accepted without modifications or any fitting all the following parts in SS:
Kimber Extended thumb Saftey
Wilson Slide Stop
Wilson Combat 'Tactical' Mag release
Ed Brown Rebuild kit (Mainspring Cap, Mainspring Housing Pin Retainer, Hammer Strut Pin, Hammer Pin, Sear Pin, Mainspring Cap Pin, Magazine Catch Lock, Safety Lock Plunger Assembly, Barrel Link Pin, Ejector Pin, Mainspring Housing Pin, Mainspring, Mag Catch Spring) ( I did not change the barrel link pin)
Wolf Single spring Recoil spring, mainspring, and Firing pin Spring
I also installed a SS Wilson Grip safety, which did require a bit of shaping to clear the hammer.
Basically, everything but the barrel, bushing ,and link, the Firing pin, Firing Pin Stop, Ejector, extractor, The series 80 parts, Sear and Disconnect, Trigger and Hammer, the frame and slide, have all been changed out.
Barrel, FPS, Ejector and Extractor are changeing afte I Electroless Nickle plate the frame and slide. Those parts I expect to have to fit- but most of it will be doable with a file.