Inside the frame is a steel bar that rubs against the side of the polymer frame. It takes a few thousand trigger pulls to really smooth the 2 surfaces together.
Field strip it and work the trigger a bazillion times while reading THR or watching TV.
Or
Do what I did and just take it out a shoot it a few thousand times. My bone stock .22/45 w/well over 30K rounds has a very nice silky smooth pull that my newer .22/45 w/only a few hundred rounds doesn't have yet.
After getting the 2 surfaces mated in well, I find a dab of grease AND a drop of oil keep that action silky smooth. Actual trigger weight ins't any lighter, the action is just a whole lot smoother.
IMNSO, the polymer frame of the .22/45 and the way that bar works against it,, will always have an advantage over the steel framed Mark II when it comes to a smooth trigger. I shot a full blown Volquartsen Mark II once. While it was a nice crisp action, it wasn't anywhere near as smooth as my well worn in ( and bone stock) .22/45.
Having the Volquartsen parts in there should make yours a real dandy once it's worked in.