:rt th
As far as the heavy trigger pull,... does the trigger pivot on a "pin" through the stock, or is it mounted on a trigger plate?
If the trigger "fulcrum" is 1/2 inch or more (the distance from where the sear bar contacts the trigger bar),... it might be possible to "re-drill and re-pin" the trigger further back to lighten the trigger pull,... that is,... "if" the trigger is suspended from a pin through the wood.
You'll just have to "study" the geometry of the trigger to see if it allows for any sort of modification to increase leverage on the lock's sear bar.