So, what isn't factory?

What did you do to the 1911?  What was done by Springfield.

Well,what IS original to the factory is probably a better question. 

The bushing, the sights, the barrel link, the recoil spring, the hammer-disconnector-sear, of course, are all new.  The grips and mainspring housing I did before.  The slide stop, the safety, the trigger are new.  The recoil spring guide has been modified, as has the frame and slide and barrel.  Hammer strut and leaf spring are new.  As are the firing pin stop and extractor.  The ejector gave me fits.

The magazine catch and firing pin and sear pin are original to the gun.

And I had loads of fun learning and doing.  But I never want to think about the money spent to make it all happen.