I do trigger jobs on 1911s and other select guns, but as I no longer have an FFL, I do only local, by appointment work. It can take several hours to modify existing parts, much less time to fit drop-in parts.
Don't forget the liability issues. If this is a carry or HD gun, making the trigger smooth and crisp is one thing, making it (much) lighter is another... and wanking it up so that it is unsafe is something else entirely.
As it has been stated already by previous, and some knowledgeable, posters... there are lots of alternatives. Compare what a competent 'Smith will charge, parts and labor, to the cost of a drop-in kit.
This is assuming you have the mechanical aptitude to install a drop in kit... and applies as well to buying the tools and supplies.
I have a tidy investment in trigger tooling, which have paid for themselves many times over... but that was my intention.
A suggestion. Detail strip and clean your gun. This will be a good learning experience if you've never done it before. If you need to, take pictures of disassembly as you go, so you will know the orientation of parts. Take notes and make little sketches if necessary.
Assemble the trigger, hammer and sear parts only... and stare at them for awhile. You may be able to, if your careful and have the appropriate size dowels, assemble them to the
outside of the gun... makes it a little easier to visualize. See how it all works?
Now... using the appropriate gun lube of your choice, when you reassemble the gun, detail lubricate the bearing and axial surfaces of those and any other parts that they come in contact with.
When you operate the trigger again, I guarantee that the pull will feel "better"... with no modification of any kind. Bonus is, you have a much greater understanding of how your gun works.
Cheers,
C