Hi Allan,
I've been off the board for awhile and just saw this old post. I put one of the kits on my Ruger Mark III and had no problems at all. Of course I cheated! I have a friend who's really into the Ruger pistols and let him do it. It went together with only minor fiddling and we didn't have a problem with any of the springs. At the range, the new trigger is awesome. My groups definitely shrunk a noticable amount.

The only issue with it is it's now not a beginner's gun. There's no way I could let someone learn to shoot with it because it's too sensitive. I'll have to let new shooters practice with my Mosquito before even thinking about letting them shoot the Ruger.

Bottom line, head shots on rabbits and squirels are going to be easy.