If your going to do this yourself, I would start with a trigger pull gauge to see where you are. Then I would tear the gun down, do a complete clean and fully polish every part, trigger channel and then put it back together to see where that got you. Also, make sure your hammer spring is the “RIGHT” one for the load you are shooting.
This practice with give you knowledge of the internal parts and see any wear or exactly what your working with.
There are a few jugs out there that you can get. One for the sear only, one for trigger to sear mating and even some bench blocks have pin positions for the hammer to sear mate up.
I know I didn’t give you a name of a jig, but this is how I address my 1911 triggers and I’m running a reliable #3 across all mine.