For the next gun that I'm planning, I want the handle to be as high (in line with the shaft) as possible. I have a Neptonics Reef trigger mech, and the only thing that I don't like is that the spring which connects the sear and trigger is attached quite low on the trigger. So I "adjusted" it, and moved the spring up by about 1/4", which puts it just below the line release slot, and will in turn allow me to raise my handle by the same amount.
Drilling the hole was the toughest part. I found the trigger to be harder than most stainless shafts that I have drilled.