I once planned to do the same thing. A friend told me that I would end up spending more than $800 bringing a cheaper gun up to the level of a $800 gun. That was good advice and I never regretted taking that advice.
That is good advice if what you
wanted was an $800 gun. If all one wants is a 1911 that works well, it doesn't hold true. Especially if you can do a simple thing like tune an extractor.