Op, there are also long and short triggers for the 1911 Colt type pistols. Changing from one to the other also makes a difference in how your shots group.
I'm lefty and have a tendency to push to the right as well. What's helped me diagnose the problem is a lot of dry fire practice where I'm not looking straight down the sights, but have the front of the gun a bit higher. That way I'm not concerned about sight picture but can focus on really looking to see if my trigger finger is pushing/twisting the gun or if I'm pressing straight back.
I'm lefty and have a tendency to push to the right as well. What's helped me diagnose the problem is a lot of dry fire practice where I'm not looking straight down the sights, but have the front of the gun a bit higher. That way I'm not concerned about sight picture but can focus on really looking to see if my trigger finger is pushing/twisting the gun or if I'm pressing straight back.