Howdy
Believe it or not, installing a lighter hammer spring will help make the trigger pull lighter. This is because with a lighter spring, the hammer full cock notch bears down with less pressure against the top of the sear (the tip of the trigger that holds the hammer back). With less pressure against the sear, it has less friction to overcome as it slides out of the notch, and this results in a lighter trigger pull.
Another thing you can do is the 'poor man's trigger job'. Very simple. Make sure the gun is unloaded. Cock the hammer. Then, shove firmly against the hammer with your thumb, trying to force it forward, while very slowly pulling the trigger until the hammer falls. What this does is force the surfaces of the sear and the full cock notch together under great pressure because of the leverage involved. As the two surfaces slide past each other under pressure, minor roughness gets smoothed out. This is called marrying the surfaces together. It does not lighten the trigger pull per se, but it makes it smoother. Just perform this operation about three times, no more, you won't get any more benefit out of it after that. Don't try this with a Colt type lockwork, you may break something, Ruger parts are sturdier.
Regarding polishing the parts, go very carefully. First of all, it does no good to polish surfaces of parts that do not bear against anything. The part surfaces are just traveling through air. Only polish flat surfaces that bear against each other, like the sides of the hammer where they rotate against the frame. Be very careful doing this, you do not want to remove much metal. Do not use a file. Use a stone. Also, it is not necessary to polish parts to a mirror finish. Just lopping the tops off of the rough surfaces is all that is necessary. That way, you leave behind the 'valleys' that can then function as oil reservoirs.
DO NOT TOUCH THE FULL COCK NOTCH, SEAR SURFACE ENGAGEMENT. Leave it alone unless you know exactly what you are doing and have worked on triggers before. It only takes a few strokes of a file to make the gun dangerous.
Personally, I don't hold with that business of disengaging one leg of the trigger spring. I never do it on any of my Rugers. The spring is designed to press the trigger forward evenly, not thrusting to one side. If you want, you can buy a lighter after market trigger spring, or slightly bend the stock one.
, I've done this with all my Ruger revolvers and have not noticed any side affects (pun intended).... other than what I expected.... Granted I haven't wore out any of my guns yet.... so don't know the 'looooong' term affects 
. And you have a spare leg if the other one breaks 
. Works well for me. YMMV.....
