Can't answer your question but, since you mentioned why you want it lighter, I'll make some pertinent comments. First, having carried revolvers exclusively for near 40 years, I've learned to not tamper with factory DA trigger pulls.
Secondly, my wife has arthritis and lately finds it impossible to shoot DAO. In fact, she found it too difficult to even cock her old snubby with it's narrow little hammer. She now has a wide spur hammer and practices rapid single fire shooting. All things considered...ease of use, accurate shot placement, confidence boost, etc.... it's no setback at all.