First of all...what is your desired outcome?
I have found the 1911 handgun to be most adaptable and versatile. You can get the arm to do almost anything you want--short of sitting up and barking, and it will do that if you feed it a proper diet of Bullseye and Unique powders.
Seriously, what do you want to do? I do 99% of the work on my 1911's--but then, I started working on them about 30 years ago.
Do you want accuracy? How much?
A pistol that is easier on the hands to handle? Do you want reliable, flawless feeding?
To realize the full potential of the pistol, here's an example: I purchased a second hand Springfield GI model--loose, clunky and nasty with an atrocious trigger. I sent the gun off to a pistolsmith that specializes in building excellent competition guns for NRA Conventional Pistol.
He sent back a gun with NO play or slop, Bo-Mar sights installed front and rear, a Bar-Sto barrel installed with an Ed Brown bushing; took the trigger pull to a clean 4 lb. pull, and checkered the front and back at 20 LPI.
The gun will shoot a 5 shot 1.5 inch group at 50
yards. Yes, I said YARDS.
The installation of parts can be simple--once you know how to do it. However, they are VERY easy to screw up--and once you do, you have to buy another part and start again. (Please--don't ask me how I know.
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If you have never worked on the 1911 pistol, but have a knowledge of machining and hand tools, you can do it if you can follow instructions. If you do not have these skills--or the patience to do a lot of painstaking detail work--you would do well to send the gun to a good pistolsmith.
Mr. Hunter, who has already posted, has an excellent reputation as a pistolsmith. There are others as well that will do an outstanding job.
However, if you're the impatient sort, the only handguns I know that are built well enough from the factory to hold the X ring of a bullseye target at 50 yards or better are built by Rock River Arms (not Rock Island) and Les Baer. Of the two, only Les Baer is (to my knowledge) actively producing handguns for sale. Consider selling your 1911, and applying the cash toward a Les Baer Premier.
And, yes--I know about Kimbers, Wilsons, etc. I have not seen one yet that will, out of the box, put 5 rounds into a 1.69 inch circle at 50 yards without some extensive tweaking.